I'm not sure that it has. Facebook will move slowly to add features since Groups isn't their core offering (and probably never will be). I think it'd be quite e

I'm not sure that it has. Facebook will move slowly to add features since Groups isn't their core offering (and probably never will be). I think it'd be quite easy to differentiate yourself from Facebook Groups if you focused on adding features Facebook will not or cannot add (such as file sharing, legal or otherwise).