ReadWriteWeb

Wolfram Alpha isn't the "Google killer" that many hyped it up to be prior to its 2009 launch. Instead, the self-described computational knowledge engine takes a completely different approach to letting users find and analyze information. Rather than scouring the Web and ranking everybody's pages in the order it thinks we'd find them useful, it uses its own data sets and computational power to return detailed reports and analysis about whatever topics users query it for.

Tomorrow, the service will ramp things up a notch when its "pro" version launches. For $5 per month, Wolfram Alpha Pro will allow users to do way more with its data, as well as enable them to upload their own. The premium offering will be discounted for students and enterprise users.

When Spotify first launched in the U.S. over the summer, few doubted that the service would be popular among music fans. The real question has always been whether the company's freemium business model would manage to convert enough users to paying subscribers. It's still relatively early, but so far things look promising.

More than 3 million people are now paying to use Spotify, according to the Financial Times. That's a conversion rate of more than 20%, a figure that has reportedly increased by 5% since the service hit 1 million users last year. In other words, not only is Spotify itself growing, but the rate at which people sign up for a premium or unlimited account is also increasing.

Enterprise social networking service Yammer today released a new version of its iOS app. The new version adds threaded discussions, private messaging and full Retina Display support. Also, users will now be able to view documents from within the app.

Yammer announced today that its social enterprise products are now available in Dutch, French, German, Japanese, Korean and Spanish. The company plans to add support for a new language each week via its Translations application, which lets users participate in the translation process. There are currently 94 languages available for translation via the Translations application. According to the company's announcement, 55% of Yammer's traffic comes from outside of North America.

As expected, Salesforce.com announced a freemium version of its enterprise collaboration product Chatter today. Chatter Free will use an invitation model. Any Chatter user will be able invite any colleague to Chatter, even if that colleague isn't already a Chatter user. We selected Chatter as ReadWriteWeb's new enterprise product of the year. Update: Marc Benioff announced during his keynote that in addition to Chatter Free, which is free for all colleagues of Salesforce.com users, Chatter.com will launch in February, 2011. Chatter.com will be free for anyone.

Salesforce.com CEO Marc Benioff reportedly told analysts today that the company will announce a free version of its enterprise activity stream product Chatter at the annual Dreamforce event in San Francisco next month. The revelation came in a conference call with financial analysts to discuss the company's third quarter financial results, according to CRN. Benioff confirmed the story via Twitter this evening. Salesforce.com currently offers Chatter for free to Salesforce.com users or for $15 a month per user for non-Salesforce.com users. Benioff described the free, stripped down version of Chatter as a "virally based product."

Several years before pronouncing that the " web is dead," Wired's Chris Anderson also predicted that "free is the future of business." (Don't let your skepticism about one assertion cloud your judgment of the other.)

Certainly "free" - and by extension "freemium" - has become one of the most popular pricing models for web companies. Evernote, Pandora, and as of yesterday SlideShare are among the companies that offer customers some version of their product for free, with additional features and services for a premium fee.

For many new Internet companies these days, "freemium" business models that hook users with free services and offer extra functionality at a price have become very popular. Today, presentation sharing service SlideShare is the latest to switch to this type of model with the announcement of its tiered PRO plans with new and advanced features starting at $19 per month.

After many months of rumor and speculation, Hulu announced yesterday that it will be launching a subscription service. Hulu Plus will give users access to more content on more platforms for a monthly fee of $9.99. And while it's surely not the most reliable metric, early reviews from the App Store indicate that some folks aren't too pleased with the change. The app (which is free) has a whopping one star rating, and the service itself has received mixed reviews.

In an email to staff yesterday, new Ning CEO Jason Rosenthal wrote that "When I became CEO 30 days ago, I told you I would take a hard look at our business. This process has brought real clarity to what's working, what's not, and what we need to do now to make Ning a big success." With that, he announced Ning would be abandoning its longstanding business model and discontinuing non-paying sites on its network. In light of this, is it time to reevaluate and reign in some of the excitement about the freemium model for startups?