To be specific HE did not cash out. An independently managed PAT cashed out.

Not if you don't care anything about the stock price or money. He just made 1.13 bln dollars for his company. If he invests it directly in fb related growth he no longer has to worry about what NASDAQ does. He's making fb independent of the media fluctuation or the fact that he has shareholders for all. The question becomes, what would you do if you you had a successful company and you were just given 1.13 bln dollars without any strings?

This is just a thought experiment, but I think fb brilliantly played wall-street and now has enough money to build an infrastructure. Internet advertising isn't creative, so what will the "next gen fb" look like? And is it worth investing in, speculating that it means nothing to them.

He still has much, much more tied up in facebook. The fact that he's diversifying his holdings shouldn't be held against him; any reasonable person would do the same to hedge against a possible decline of the entire technology sector in the event social media company valuations face some sort of "correction". Also, anyone with that much money in equities has to worry about broader macroeconomic issues such as the current problems in Greece and the rest of the Eurozone. Once again, Zuckerberg isn't doing anything that should be held against him. He still has most of his eggs in the facebook basket; he's merely being prudent.

It would be very cool, though.