Relationship Update Stream
http://updates.elsewhere.im/

The Relationship Update Stream is an endless feed of social relationship data, designed for web services to be able to send and receive information when changes to social relationships on their service occur. This is a developer platform, not something for regular users. Relationship Update Stream features include: a) Allows all open services to share public relationship data, b) Provides real-time updates about changes to public relationships, c) Makes it possible for services to both publish and subscribe to public relationship changes, d) Data quality is high since services have to vouch for the data they provide, e) Designed by developers, for developers, and f) Builds on top of the Atom Stream format that’s already seen strong adoption and has existing client libraries. This has been added to Social Informatics Subject Tracer™ Information Blog. This has been added to Script Resources Subject Tracer™ Information Blog.