OK, now that we've established that surface matters and language matters is it ok to dissect game changer hopefuls like Ning?
It looks to me like a well done, well integrated advanced web panel for a well equipped PHP hosting solution. What that means is: You use the webbrowser to configure and manage your hosted application. You can rely on certain pluggable elements that will fit right into your data (e.g. user login) but other than that you're writing PHP agains a set of compatible elements accessing e.g. all the open social services out there.
A server with a full CPAN, a web interface to my CGI directory and something like Catalyst would seem to do almost the same trick. Or the equivalent based on Rails.

But of course execution is everything and ideas nothing in this particular case. Looking forward to testing this - even if i do have to learn php.