XKCD's map of online communities (2007) (Note the size of size of MySpace in this 2007 version as compared to the size of Facebook in the 2010 version at http://xkcd.com/802/ )
Live blog & stream of Mark Zuckerberg's first live interview since the company went public in May. Interesting points about Facebook's shift to mobile focus ("We're a mobile company") and Instagram acquisition...