If you look at the headaches Zuckerberg is running into now, even with, ostensibly, "total control" over a public company, it just seems like an extraordinary distraction from keeping your users and employees happy.
Speaking of Facebook, there is also the issue they ran into with having over 500 shareholders and staying private. I'm assuming that there is some way to guarantee revenue sharing to employees without making them actual shareholders, so that you wouldn't step over the 500 employee threshold and trigger the SEC's required IPO - assuming you were lucky enough to get that big.