Since you’re probably a little Googled out with the barrage of announcements coming out of I/O Wednesday, we’ll keep this one brief.
The Buzz API is still branded as a “Labs” release, so you can expect things to change over the coming weeks. But it’s already looking fully-formed. It offers full read/write support with Activity Streams, AtomPub, OAuth, PubSubHubbub and JSON. So if you have a website or app that lets users publish status updates, images, or any sort of activity using the actor/verb/object model, then you can integrate Buzz updates into your offering.
Authorization happens through OACurl — learn more about it with Google’s OACurl cookbook.
The bulk of the Buzz API features were discussed at a developer’s session on Wednesday afternoon. You can read notes taken by attendees by launching a Wave from the session (What is this, the future?).