ReadWriteWeb

Calais, a project sponsored by Reuters offers a few handy plugins that enable you to use its API to auto-tag all the posts in your blog (see our coverage). It goes through your content, extracts the relevant keywords, and adds those as tags in your CMS.

But Open Calais isn't open source. Here are a few open source tools you can use to extract key terms from text. As far as I know, none have been turned into CMS plugins... yet.

Facebook announced today that it is launching a feature where users can tag Pages in photos. That means users can now tag brands, businesses, musicians and personalities in their photo streams. Take a picture of your friend holding Pabst Blue Ribbon while dancing at the club? You can now tag your friend and the beer.

The tags will appear on the "photo" tag on the Facebook Page, not on the walls and can be tagged by anyone on Facebook, not just people who have liked that page. For the start of the feature, only Facebook Pages with the "brands & products" or "people" categories can be tagged in photos. Facebook will look to expand that to more page categories over time.

A recent report released by research consultancy PSFK looks at the key trends occurring within the mobile tagging space - that is, the trends associated with the use of mobile barcodes, QR codes and Microsoft Tags. In particular, the report looks at usage and development from the branding and marketing angle, to determine the many ways in which companies have adopted barcode tagging to better communicate with their customers.

While that may be too narrow a focus to dub the report "The Future of Mobile Tagging," as it's being called, it's an interesting read nonetheless. We've included it below courtesy of Slideshare, so you can read through the report for yourself.

Any of Facebook's over 400 million users will immediately recognize some new features on popular Twitter photo-sharing service Twitpic today as users can now tag people in their photos. In a blog post this morning, the two-year-old company announced it had passed the 10 million user mark and that it sees 40 million unique visitors each month. The company says it is releasing its Face Tagging functionality "to show [its] thanks" to the community, but could it bring headaches and worries with it too?

Gmail Labs, the "Settings" section featuring optional, experimental features for Google's webmail program has just received two new additions: "message sneak peek" and "nested labels." Now the sneak peek we definitely like - it lets you preview a message without opening it so you can take immediate action. Handy!

But nested labels is a somewhat curious addition. It turns Gmail's once-revolutionary "tagging" system into something that more closely resembles the traditional folder structure found in email programs like Outlook. So now you can drag-and-drop your email into these so-called labels and you can create hierarchies, too? Oh, c'mon, Gmail, let's just call them folders already and be done with it.

A spin-off of Finnish software development company Nodeta, Flowdock aspires to help developers and others sift out actionable bits of knowledge from ongoing conversations and make them retrievable. Their team messenger services allows separation and tagging of conversational elements.

"In Flowdock, the epiphany comes when you tag a chat message for the first time," Nodeta and Flowdock's CTO Otta Hilska wrote us. "You realize how you just took a piece of conversation and turned it into a nugget of knowledge. Somebody talked about a bug, and you turned it into a bug report. Or pasted a snippet of code, and you categorized and organized it. The real validation for the concept comes when you are looking for some other snippet of code, a link to a partner, an eBook or something else and come to think 'I wonder if it's tagged in Flowdock". Sure enough it will be.'"

The book and media industries are going through interesting times, to put it mildly. As physical books prepare for their demise, the confusion around pricing of digital ones grows. Yet, whether physical or digital, to sell books you need marketing. People need to hear about a book before they buy it.

This is where the book review come in. Every publicist and publisher's dream is to land a positive review with an authoritative source. A good review in The New York Times or the L.A. Times used to be a pass to big figure sales. Sounds like it still should be, but it is not, because most book reviews are poorly formatted and cannot be recognized by Google and other software.

Facebook just launched status tagging for friends, pages, events and groups. The company has torn a page out of the Twitter playbook and plans to increase search functionality via the @ tag. Over the next few weeks Facebook users will be able to tag their friends, pages and groups in status messages. Similar to photo tagging, all those indicated in the tag will receive a notification. Said Facebook product manager Andrew Huang to Inside Facebook, "People use status updates to tell stories about real world experiences. This is about making the site more engaging."

It was two years ago that we first heard of Zigtag, a service that promised to "transform how people search, save and share knowledge & information." Now, after a nine-month private beta, this semantic tagging service has finally launched. But is Zigtag's bookmarking tool intelligent enough for 2009?