Well, one is for sure: Zuckerberg was very lucky that Instagram owners were not mini-Zucks. Scared to think what will happen next time when Zuck needs to buy a competitor and they owner will greet him with: "Hello, Mr. Mark, I am Bark, CEO of X, Bitch!"
Not the stock I'm concerned with. It's the fact that 1 in 8 people in the world now use Facebook monthly. When that becomes 1/3 or 1/2, what happens? A successful IPO can make that happen.