In a session here at Google I/O called "What's the hubbub about Google Buzz APIs," Google announced, well, Buzz APIs.
The session was aimed at "taking a deep dive into building with the Buzz APIs and the open standards it uses, which include ActivityStrea.ms, PubSubHubbub, OAuth, Salmon, and Webfinger."
Chris Chabot, developer advocate at Google announced the launch and a number of partners that have helped the company get it started. Among these: Seesmic, Tweetdeck, and Ping.fm.
The Buzz APIs were introduced under the labs label, as Chabot says, "a few things still need to be developed. We're still talking to the community."
The APIs utilize Acivitystrea.ms, which defines who performed the action, what they did, and when. There can be other bits of info like mood, context, or location. Everything is geo-enabled.
With Buzz, you can choose whether you want your posts to be completely public or if you want particular people to be able to read them. There are precautions taken within the code that prevent private posts from being used in the APIs. "We don't want to accidentlly expose private data," says Chabot.
Documentation for the Buzz APIs can be found here.