I'm gonna repeat my usual spiel here: use Bitbucket. Github's only real benefit is its network graph - I'd like to see Bitbucket implement that. But I jumped ship to Bitbucket a while back so I could get attachments on my issue tracker and never looked back. Free private repos too. And for a "social coding" site, Github doesn't have very much social stuff going on. There's no forum - just some lame web form for feedback that Github never seems to respond to.
Oh and I remember seeing a talk from one of the main Github developers some time ago and he kept saying "fuck" all the time like Beavis & Butthead. Not impressive.