Our role is to be a platform for making all of these apps more social, and it's kind of an extension of what we see happening on the web, with the exception of mobile, which I think will be even more important than the web in a few years - maybe even sooner.

The web is at a really important turning point right now. Up until recently, the default on the web has been that most things aren't social and most things don't use your real identity. We're building toward a web where the default is social.

Back, you know, a few generations ago, people didn't have a way to share information and express their opinions efficiently to a lot of people. But now they do. Right now, with social networks and other tools on the Internet, all of these 500 million people have a way to say what they're thinking and have their voice be heard.

Facebook is shaping a broader web. If you look back for the past five or seven years, the story about social networking has really been about getting people connected. But if you look forward for the next five years, I think that the story people are going to remember five years from now isn't how this one site was built; it is how every single service that you use is now going to be better with your friends.

People will always want more immersive ways to express themselves. So if you go back ten years ago on the internet, most of what people shared and consumed was text. Now a lot of it is photos. I think, going forward, a lot of it is going to be videos, getting richer and richer.

When I'm introspective about the last few years I think the biggest mistake that we made, as a company, is betting too much on HTML5 as opposed to native... because it just wasn't there. And it's not that HTML5 is bad. I'm actually, on long-term, really excited about it. One of the things that's interesting is we actually have more people on a daily basis using mobile Web Facebook than we have using our iOS or Android apps combined. So mobile Web is a big thing for us.