This is great to see so many people getting serious about this. I have been waiting and thinking about this myself for a long long time...
First I found the WIRED story
http://www.wired.com/software/webservices/news/2007/08/open_social_net
...with links to this below...
Brad's Thoughts on the Social Graph
Posted by sinergi at September 4, 2007 04:43 PM