It's unbelievable that it's only been 2 years since GitHub launched. And what has all happened since then... More and more projects are leaving the dark days of centralized systems behind in favour of a more open approach. If you think about it, it's been 5 years since Google Code launched so GitHub is still relatively new but it definitely doesn't feel that way. Back then it was also way more of a revolution than an evolution if you compare it to Google Code vs. Sourceforge.
Nowadays, sites like GitHub and Bitbucket start to feel - at least for me - like the central hub of the opensource community. The place where you find new and interesting projects and where you can easily contribute. And btw.: They even have a podcast ;-)