"You take this data, mash it up with any other very large corpus of data with timestamps," Flip Kromer of data marketplace Infochimps told us, "and you've got a web app." Today's announcement of the availability of location data means the same thing: you take this data, mash it up with any other data with location information and you've got an app. From Digg or StumbleUpon for your favorite coffee shop to political and disease tracking - there's a whole lot that's possible.

Users will have to be both prompted and incentivized. Fortunately, a location-aware Twitter experience is something that will enable developers to deliver value to individual users immediately and in isolation - it doesn't have to be one of those situations where "this will be cool once other people I know are using it."

With the announcement today of Twitter search results being added to Yahoo News searches, Twitter data is now being used by all three of the major search engines. (Google's implementation is still forthcoming, but the deal is done.) It might be one of the big players, but it's more likely to be small innovators that make creative use of the new location data.

These are possible Twitter use cases, but the standardized Activity Streams spec that Facebook, MySpace, Netflix and others now support also includes a geolocation field - so if the walls around Twitter ever fall to interoperability then we could be seeing innovations like these across all kinds of networks.

Here are some of the kinds of things we expect, or would like, to see.

"Party Over Here" Bot: Automated Geo-Replies

Want to know when you're near a certain type of public event, great wine shops or deals at Macy's? How about when friends, close friends or friends-of-friends are near? It's not hard to imagine a bot that you subscribe to on Twitter, that then auto-subscribes to you, notices when you "check in" at a new location and automatically sends you a reply when whatever or whomever you're interested in is near that location.

There are all kinds of bots built on Twitter already, but one that can mash-up your physical location with its data store is going to be a lot more useful than a bot that tells you when a sensor noticed your plants need to be watered.

These are the kinds of services that will incentivize Twitter users to expose their location data. Assuming a substantial number of people make that choice, here are a few other examples that come to mind.

Articles Being Shared From This Coffee Shop Today Include...

Think people just stare at their computers in public these days? A service like this could shake that up. How about a StumbleUpon implementation that lets you stumble and read articles from people who've Tweeted from the same place you're in. Imagine walking down the street and considering two competing coffee shops; what's been on the reading list of each today?

News at 11: Local Interest Survey Tool

Think local TV news and newspaper companies would be interested in a stream of hot topics in their local area? They'd be foolish not to; what a great way to discover breaking local news to report on.

Does your local newspaper print a selection of letters mailed-in each week, but list the number of total letters received on the hottest topics? Imagine capturing that local chatter from a much larger sampling of people. Local tweets plus an entity extraction algorithm.

Cop Watcher

Imagine taking a map of tweets discussing criminal activity, or police misconduct, in a city and comparing it with a map of the same from local police agencies. Some places that warrant more official attention could be exposed.

Inventory Forecast

If people in a certain city are twittering like fiends about a new product hitting the market, store orders, marketing and other parts of the supply chain could benefit from an earlier warning about it.

Politics & Marketing

People in Oregon are sharing a Huffington Post article about today's health care reform announcement a lot? In Seattle, Washington perhaps not so much? Political organizers of a certain persuasion could find that information actionable.

How about unearthing Twitter users posting about environmental issues who also live in areas with environmental issues that an organization is working on.

Want to measure local effectiveness of marketing campaigns? Imagine Radian6 or ScoutLabs using the location API. That's only a mater of time.

Flu Trends+

Think Google's use of search data to map out global disease trends is cool? Why stop there? How about pro-active messages (via Twitter) when there's an increase in messages about being sick in your area?

Of course all of this will work better if more people are using Twitter and if people expose their location data, but that may very well happen. Prompting and individual incentives could be big drivers. The degree to which Twitter data is open for analysis by outside parties is a huge asset.

What would you like to see cross-referenced with Twitter location data?

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Typical of what we like to think of as the company's "mysterious charm," the feature has been unveiled six months later with a brief post on the Twitter blog. The new geotagging capabilities can already be seen in certain third-party apps and might even come to the web interface sometime soon.

Apps such as Birdfeed, Seesmic Web, Foursquare, Gowalla, Twidroid, Twittelator Pro, and many others are already supporting location-based data for tweets.

"The added information provides valuable context when reading your friends tweets and allows you to better focus in on local conversations," writes Twitter platform/API man Ryan Sarver in the blog post.

"Now you can find out what live music is playing right now in your neighborhood or what people visiting Checkpoint Charlie are saying today about the anniversary of the Berlin Wall. These are only the beginning and we are really looking forward to seeing the creative uses emerge from the developer community."

As are we! But we might hold out on enabling the geo-tastic feature just yet. We've still got a few stalkers to shake, and we're waiting for the inevitable bugs to surface before we trust our favorite microblog with our favorite haunts, too.

If you want to try it, don't forget that it takes two steps to activate the feature. First, go to Labs and enable the feature. Then, go to your signature settings and check "Append your location to the signature."

Bear in mind, it's a Labs feature, so it's not without foibles. The location, for example, is based on IP detection. So it may not be as accurate as you would like - like if the corporate IP address of the connection you're using is attributed to a different location. Want more accuracy? Install Gears so the location module can use wi-fi access points to hone in on your whereabouts.

Don't want that certain someone to know that you're not where you'd said you would be? Simply delete the location line before sending the message. (The signature and location are appended to the message when the composition window opens.)

VentureBeat and its readers were wondering why Google didn't tie this feature to Latitude. We were, too. But we're guessing that - given that this was a Google 20% project - the two were on separate trajectories. Perhaps if "location in the signature" ever makes it out of Labs, it will leverage Latitude.

If you're into testing geolocation features - or letting people (and Google) know where you are - this could be the Gmail feature you've been waiting for.

With the rise of smartphone-based computing, applications like Brightkite, Loopt, and others were slowly growing their user base, letting friends share posts, photos, and other information with each other as they moved from place to place out in the real world. Accessed via mobile applications or SMS, these sorts of networks provided the framework for connecting people to the places they visit.

However, it was too soon to determine whether mobile social networking was a space that would ever really take off. As studies showed, the social networks that most people accessed on the go were not specialized "mobile" networks, but the usual ones - Facebook and MySpace. Having to recreate a friend graph on new mobile social networks was not something everyone was up for...at least it hadn't been not so far.

Without any easy way to import MySpace and Facebook friends to these newer mobile networks (like via Facebook Connect for example), our mobile social networks were filled only with an odd mix of friends: some early adopters and maybe a handful of tech-obsessed locals. But that being said, the networks still had potential assuming they could have ever gotten over the initial hump to gather critical mass. They were offering something unique, and that boded well for them. Being able to tune into the world around you and see who was there, who had been there, and what was going on was a type of augmented reality that was never possible before the advent of modern mobile computing.

Google's Potential to Dominate

Now that Google has come onto the scene, friend graphs already intact, one has to wonder about the impact this will have on these smaller networks. How will they survive? Google is already a mainstream service and Latitude was just covered by the Wall Street Journal. Needless to say, any mainstream users out there intrigued by mobile social networking will now just go try Google's service.

Yet where the smaller networks had the cozy feel of you and handful of friends, any service maintained by a behemoth such as Google immediately has a "Big Brother" feel to it. No matter how many opt-out features and privacy controls they offer, some people just won't be able to shake that feeling that Google is just a little too omnipresent in our lives. But will "fear of Google" alone be enough to keep people from leaving the small mobile networks in favor of the larger one?

According to Martin May, Brightkite founder, though, Google didn't even come close to killing his service. "With Brightkite," he says, "we are primarily focused making meaningful connections with people you didn't necessarily know yet, around places. Latitude seems focused on showing you where your existing friends are at. Functionality-wise, Latitude does very little beyond sharing a latitude, longitude and accuracy with friends at the moment." But even May admits that may change down the road.

Wait...Our Real Friends Aren't on Google

What's strange about the mobile social networking market, though, are the missing players. The major missing players. Where is Facebook? Where is MySpace? Why is it that the biggest social networks on the planet have decidedly shunned any attempt to add proximity and mapping to their mobile services?

If anything our real friends are here, not on Google, whose friend network includes random people from our Gmail accounts, interesting folks from our RSS readers, and the occasional visitors to our blogs (thanks to the Google Friend Connect widget). Those may be people who we work with, people who wanted to share feeds with us, or fellow bloggers, but they aren't necessarily our real-life friends. And since they're not, why on earth would we want to share our locations with them?

The ability to connect to all our real-life, real-world friends and family - friends that include mainstream web users, mom, dad, and the kids - is something that just isn't here yet. No matter which mobile social network you end up using, including Google's, you're only going to see a slice of your actual social network. A true mobile social network would integrate friends from all the major social networks we participate in, plus our bevy of work colleagues from the social network hidden in our email, and, for all those non-participants out there, it would let us add them via their mobile phone number. But that really would be creepy, so we sort of hope it never happens.

Knowing where people are is great. Being able to get ahold of them is even better. That's why Latitude also lets you interact with them by providing access to SMS and IM or allowing you to call them.

It's All About the Data

While many of us have grown used to providing details on our travels by updating location-aware apps like Brightkite or checking in with sites like Dopplr, those journeys have always been loosely affiliated with the rest of our habits - through a lifestream, at best. Today, with Google gathering this information, it changes the picture entirely.

For millions of users, Google already knows how they search, what they click, what they buy, who they know, how they communicate, and where they go on the Web. Location enables them to add another critical data point - where they are when they're performing any of those actions. So if you think Google has too much information about you already, you've got another think coming.

Long story short, Latitude adds a whole new level of complexity to Google's understanding of you and your habits. And while we'll no doubt derive some very interesting benefits from sharing that information, we should hold no illusions about the value of that data to Google and its efforts to run a profitable business.

But, in Google's defense, they've also worked to ensure you have a way to opt out of the service and maintain complete control over your privacy. Katherine Boehret of The Wall Street Journal, who has had the opportunity to test drive Latitude for the past week, also gives a nod to those opt-out features:

"Usability issues aside, location-based services like Latitude can be just plain creepy, especially when a Big Brother like Google is tracking your whereabouts. So Google incorporated easy-to-change privacy settings so that locations can be automatically detected, manually entered or completely hidden from other people. Or people can sign out of Latitude altogether."

Do No Evil, Please

It was only a matter of time before Google entered this market, and no doubt millions of people will soon be flooding the service with their up-to-the-minute location details. With the combination of Google Maps, Google Latitude, Google Friend Connect, and Android, it's not very difficult to begin daydreaming about the potential for this service.

But it's also a leap of faith as a user, entrusting Google with yet another piece of data that helps them figure out the puzzle of understanding you - and how and where you're likely to perform actions that put money in Google's pocket.

It will be interesting to see where Google goes with this one - and interesting to see where you're going, now that we can look over your shoulder.

Update: See our follow-up analysis Did Google Just Kill All the Other Mobile Social Networks?

Windows Mobile Only and not a lot of GPS

Looking at the list of supported phones, it is noteworthy that very few of them can actually perform location detection via GPS, though the list of phones that can support detection via cell-ID is relatively large. Using cell-phone towers for location detection, however, can be highly inaccurate, especially in less populated areas. Within cities and most suburbs, though, it tends to work reasonably well. On the other hand, given that a lot of users are very concerned about the privacy implications of location-aware software, maybe having a system that is not 100% accurate might just diffuse some of these fears.

Google also announced two partners in the UK that have already implemented the Geolocation API into their products: the UK version of travel site lastminute.com and the social discovery tool rummble.com.

Fire Eagle

It's important to point out that while this product seems similar to Yahoo's FireEagle at first glance, Google's product is really more basic, in that Yahoo not only provides the location API, but also wants to function as a central clearinghouse for location data and data exchange between different application.

Soon to be Ubiquitous

As we have pointed out before, we think that location-aware software is going to be one of the most interesting markets to watch in the near future and as as location-aware devices become more ubiquitous, we will hopefully see a lot of new and innovative services make use of them, as long as developers can assure users that they can mitigate the potential privacy implications of these apps.

However, it is important to note that Yahoo has made privacy a central focus of the platform and right upon sign-up, users are given the option to receive regular emails from Yahoo to see if they are still comfortable with sharing this kind of information. If you do not respond to this email, Yahoo will automatically disable your Fire Eagle account. Yahoo also allows users to turn the service off when they want to keep their location private.

Upon launch, Fire Eagle seems to be having some trouble with keeping up with the sudden rush of new users, as the service was sometimes unable to pinpoint our location. Once it is running smoothly again, we would not be surprised if Fire Eagle could make good on its promise of becoming the central clearinghouse for location services. Already, close to 800 developers are working on applications that make use of Fire Eagle in some form or another.

The first two apps to engage with Fire Eagle is Dopplr, the super-hip social-travel app, and Danger Day, a service for updating your location on Twitter. Others are ramping up quickly, though Fire Eagle is still invite-only. We've got invite URLs posted at the end of this post, knock yourselves out. The Yahoo! Group for developers interested in Fire Eagle is here.

First, Yahoo! put privacy right out front. Many people want their data to be portable from service to service and many people want that to include their location data from mobile or other interfaces. I personally don't want my location broadcast automatically, at all, to anyone thank you very much. Fire Eagle has privacy and user control of data written all over it.

Users have the option to hide themselves with a single click, they can click to purge all their data from the Fire Eagle databases, the service even lets you select how often you'd like to receive an email reminding you that it is tracking your location as asking you to confirm that you want tracking to continue. By default you're emailed once a month for consent to be reconfirmed! Hello trust building measures! It's almost enough to make me interested in exposing my location, selectively.

Second, the way Yahoo! is developing its Platform is great. It's offering API kits in five different programming languages, it's got user authorization protocols already available for web, desktop and mobile apps and it's using the open standards community built oAuth to facilitate faster, more secure mashups. We wrote about oAuth's launch here and Google is also using it extensively in OpenSocial. This aint no cry-baby do it my way or I'm taking my ball and going home framework like the Facebook platform. This is leveraging universal open standards.

Standards based platform plus strong privacy equals the best scenario I can imagine for a location tracking service. We'll see what kinds of innovative applications get built on top of it.