Google tonight is going public with Google Buzz, a big upgrade to Gmail that allows users to share interesting links, photos, feeds and videos to your contacts across the web. Check out Google’s video explanation here:

The first interesting feature that stands out to me is that Buzz will link Picasa with Flickr; yep, Google will allow Gmail users to share cool stuff with contacts on both Picasa and Flickr. It means building into one of the most creative of all online communities (Flickr, that is) a recommendation engine. That, I’m looking forward to.

From the video explanation, we get a pretty clear picture of what Google is thinking here. It wants to make email, a very private matter, a helluva lot more social. As Google’s Bradley Horowitz tells CNN, the idea behind Buzz is “to weed out what he called the clutter of other networking sites.”CNN goes on to report:

Google Buzz will automatically make “friends” out of the people a user e-mails or chats with the most on Gmail. Different settings will allow the user to make their posts public, like on Twitter, or private, as is usually the case on Facebook.

Comments on posts will appear in real time. And comments by other users will be weighted, similar to how Google’s search engine weighs results, to “collapse bad buzz and recommend the good buzz,” said Gmail product manager Todd Jackson.

This might not be for everyone. But I’ll be anxiously checking my in-box for the invite.