Google's turning Gmail into a social network with a new feature called "Buzz" that adds a handful of networking and sharing features to the company's free Web email service.

Co-founder Sergey Brin said Buzz blends social networking and productivity tools into a powerful new service.

"This is another very compelling evolution where I think you have the meeting of social communication and productivity that's closer together," he said. "I think a lot of the past services have focused simply on friends and entertainment, things like that.... I think the bridging of those worlds is very powerful."

Clicking a tab in Gmail will present a format with a series of live, streaming updates from user's email contacts, turning the user's inbox into Google's version of Facebook.

Frequent contacts are automatically converted to "followers" whose public updates, photos and other shared material appears in the stream.

Public updates will all be indexed by Google and searchable. I wonder what this will do to Gmail's utility as a Web email service; people who use Gmail for sensitive correspondence will need to be sure they're correctly using the public and private sharing options that Buzz adds.

There's also a Twitteresque mobile component, giving users the ability to post and share updates from mobile phones. It also uses Google's location-based service to add geotags to Buzz posts made from smartphones.

Also unveiled this morning was a new version of Google Mobile Maps with a layer displaying Buzz posts tagged to an area or venue.

The company also plans to launch an enterprise version of Buzz for companies to use for communicating and sharing information.

Google's presenting this update as a service to help people organize and manage the flood of online information. But that may not be enough to deflect grumbling about Google blatantly replicating the features of popular social networks.

"Organizing the world's social information has become a large scale problem, the kind Google loves to solve," Todd Jackson, Buzz product manager, said during Google's announcement this morning.

Buzz will be available at buzz.google.com and via a tab in Gmail. The company plans to make it available starting around 11 a.m. for invited users and broadly over the next few days. Here's the Google announcement with links.

Jackson wouldn't use the "F" word when asked how Buzz would integrate with Facebook and its Connect feature.

"We don't have anything to announce at this time but it's something to think about," he said.

Pressed on how Buzz emulates Facebook, Brin also declined to name the service but noted that many different social networking services have been developed, including a rudimentary one that he built in high school.

Brin characterized Buzz as the latest contribution to the evolution of social networking, saying that he hoped it's one of the "revolutionary" new technology products that have appeared every few years over the last decade.

"I think we look at this as part of a longer term evolution and trying to put together the best set of features and compelling elements to make this really successul both from a technical point of view as well as a social point of view," he said.

Microsoft - which has a stake in Facebook and provides ad services to the site - issued a sharp statement from Dharmesh Mehta, Windows Live director of product management:

"Busy people don't want another social network, what they want is the convenience of aggregation. We've done that. Hotmail customers have benefitted from Microsoft working with Flickr, Facebook, Twitter and 75 other partners since 2008."

1. Auto-following. See content from people you follow.
"There's always been a giant social network under Gmail."
2. Rich, fast sharing experience. "Buzz brings a social UI to Gmail."
3. Public and private sharing.
4. Inbox integration. (Add social updates to inbox)
5. "Recommended buzz" that adds suggested people's updates to your stream.

The Wall Street Journal first reported the story of the change on Feb. 8.

Google's Buzz introduction video:

Google's mobile Buzz video: