There's an entire universe in every single tweet, and it all really depends on the content as far as how it's going to spread.

A number of people in the United States, almost everyone, is using plastic cards to pay for things, but it's extremely difficult to accept these cards. So let's make it's easy and take more and more of the friction out as we can.

What's interesting about Twitter and the influencers that someone follows - like, say, Shaquille O'Neal - is that they see someone who is using the exact same tools that they have access to, and I think that inspires this hope to be able to really engage with someone like him.

It's a matter of invitations versus context. Twitter is really good at providing context, like, I''m having coffee at Third Rail Coffee.' Foursquare is about invitations to places. In this respect Foursquare has started to replace Yelp for me.

Revolution looks at the intersection ahead and pushes people to do the right thing.

Constraints inspire us in how we approach the press, how we approach business relationships, how we do everything.

The strongest thing you can cultivate as an entrepreneur is to not rely on luck but cultivating an ability to recognize fortunate situations when they are occurring.