The biggest risk is not taking any risk.

People developed planes first and then took care of flight safety. If people were focused on safety first, no one would ever have built a plane.

Look at the way celebrities and politicians are using Facebook already. When Ashton Kutcher posts a video, he gets hundreds of pieces of feedback. Maybe he doesn't have time to read them all or respond to them all, but he's getting good feedback and getting a good sense of how people are thinking about that and maybe can respond to some of it.

Almost any mistake you can make in running a company, I've probably made

There are many machines throughout history that were built to do something better than a human can.

VR is a very intense visual experience and having the most powerful PC is the only way to deliver certain experiences.

Think about what people are doing on Facebook today. They're keeping up with their friends and family, but they're also building an image and identity for themselves, which in a sense is their brand. They're connecting with the audience that they want to connect to. It's almost a disadvantage if you're not on it now.