Hi all

sometime ago I had mentioned how NING had changed their UI and how  
fresh and airy it was. More than anything else it took 2 min to create  
a whole network of your choice. Well I came across this yesterday and  
thought of the whole Wordpress gang here and wanted to pass it on.  
Buddypress looks like a promising set of social networking plugins for  
the Vanilla install of WP.

its still in dev - take a look!

http://buddypress.org/

http://trac.buddypress.org/wiki/installing-buddypress