Such a plugin doesn’t exist yet.
Does anybody knows it exist next time? Is it in work?
I’m not aware of anything.
Does anybody know anything news?
Sorry, but I haven’t heard anything about it for a while. I believe the term you’re searching for is “Friend of a Friend” or, “FOAF”.
I had a BuddyPress 1.1.x era plugin that added FOAF to user and group profiles. I was trying to learn FOAF & SIOC & RDFa at the time so I have probably accidentally used some of the wrong taxonomies. It did help out on Google page rank pretty well.
So, with those provisos, here’s the link to my old SVN for the code. I haven’t looked at it in over a year so YMMV:
Old topic, but maybe interesting? I needed the same functionallity so I created a plugin that might help here, too: