An Architecture of a Distributed Semantic Social Network

An interesting paper on building a social web by sebastian trap

http://goo.gl/4FQy8

I'm trying to collate a list of people or groups that are working on social
solutions.

So far I have a rough list of about 10 projects that are strongly aligned
with linked data and the read write web.

I'm very interested to hear if anyone is working on a social solution, or
knows some good ones.

Please feel free to reply on, or off-list, and I'll send out a summary of
everything