There’s a bit at the following blog on Google’s launch it’s new social networking api:

Google has announced OpenSocial, a new open API for social networks. The new standard will allow developers to create Facebook-like apps on any social network site that implements it with the same calls.

You can check out the post here:

http://radar.oreilly.com/archives/2007/10/google-opensocial-api-launch.html