Thought experiment: Cory Doctorow becomes CEO of Facebook with Zuckerberg's entire stock allocation and equivalent voting control. Do you stand by your assertion that nothing changes?
One of two things happens:
1) Cory Doctorow gradually morphs into Zuckerberg
2) Another social network, run more like Facebook is currently, replaces the one that Cory Doctorow is running. The reason Facebook didn't go the way of Friendster, Livejournal, and MySpace, is that he figured out how to play the game (as it currently exists) better than anyone else. Cory Doctorow would be like someone trying to win the Tour de France when everyone else was doping. In this analogy, Zuckerberg is Lance Armstrong, playing the existing game the way you need to play it to win that game.