php: best system/cms for building social community system?

Question

our company needs to build up a professional social community site with extensive features like: profiles/groups/add friend, image + video upload, articles + tagging, activity stream, login/interfaces to social sites like facebook, twitter, foursquare, vimeo ..

what would be the most powerful system/extension? the most important factor would be: speed! as we also want to do most of the gui customizing by php on our own, the cms/system shouldn't be too static.

thanks

Answer 1

I will suggest you to use Joomla + Jom Social