The battle of social APIs continues to heat-up with this week's newest entry to our listings: the Friendster API. Although Friendster has been out of the headlines for awhile, they do have 50 million registered users. According to this TechCrunch report the API is currently open to developers but will not be available to live users until November 30th.
Some details on the platform: the API itself is REST-based and data is returned in XML or JSON, they currently have a widget directory and new third party apps will be listed here, and developers will be able monetize their widgets with their own advertising. Widgets must be registered with Friendster before going live and being listed in the directory.
Initially there are 8 methods available in the API, but they do provide information on friends and their social graphs. There's also a /depth:/uid1;uid2 method that gets the relation depth between two users. If you have an API key you can use their interactive API test tool.
Developers will start comparing the data that's available via different social networks. In this case there's Friendster's userinfo versus Facebook's users.getInfo:
And their documentation includes the following authentication sequence diagram showing how to a add a widget from within the Friendster site (interesting because we don't tend to see very many UML-style diagrams used when documenting Web 2.0 APIs):