Building a mission and building a business go hand-in-hand. It is true that the primary thing that makes me excited about what we're doing is the mission, but I also think, from the very beginning, we've had this healthy understanding which is that we need to do both.

Facebook is uniquely positioned to answer questions that people have, like, what sushi restaurants have my friends gone to in New York lately and liked? These are queries you could potentially do with Facebook that you couldn't do with anything else, we just have to do it.

By giving people the power to share, we're making the world more transparent.

For the first time we're allowing developers who don't work at Facebook to develop applications just as if they were. That's a big deal because it means that all developers have a new way of doing business if they choose to take advantage of it. There are whole companies that are forming whose only product is a Facebook Platform application.

The thing I really care about is the mission, making the world open.

People think innovation is just having a good idea but a lot of it is just moving quickly and trying a lot of things.

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.