Google Buzz has just been announced today. It aggregates in all the social media activity of your accounts across many platforms into your Gmail. Also, if you use Google Reader, or Picasa, or nearly any other Google service and have contacts in these places, it will synchronize back with your Gmail Contacts. In order to use it, you’ll need to configure your Google Profile.
Learn more about Google Buzz by watching Google’s video:
To see Google Buzz in action: