Advertising works most effectively when it's in line with what people are already trying to do. And people are trying to communicate in a certain way on Facebook - they share information with their friends, they learn about what their friends are doing - so there's really a whole new opportunity for a new type of advertising model within that.

There are people who are really good managers, people who can manage a big organization, and then there are people who are very analytic or focused on strategy. Those two types don't usually tend to be in the same person. I would put myself much more in the latter camp.

Openness fundamentally affects a lot of the core institutions in society - the media, the economy, how people relate to the government and just their leadership.

Advertising works most effectively when it's in line with what people are already trying to do. And people are trying to communicate in a certain way on Facebook - they share information with their friends, they learn about what their friends are doing - so there's really a whole new opportunity for a new type of advertising model within that.

There are social restrictions where someone could be suppressing someone else's freedom to express themselves.

When you give people ability to stay connected with all the people they care about, and you make it so they can express new things about themselves or in communication with other people who they care about, then you just open up new possibilities. You make it so people can stay connected in ways that they couldn't before.

The world is changing so quickly, with mobile stuff and different platforms emerging, that I think it's more likely that the biggest competitor for Facebook is someone that we haven't heard of. What that means for us is that we should just really stay focused on what we're doing.