You can't get married to any one particular plan. That is the biggest lesson I learned at PayPal.

If I see what you're up to on Facebook but I don't see your updates on Flickr, I'll still care about Facebook.

Ignore your mistakes. The number one thing to worry about is -Am I doing what I'm good at?

Facebook and Myspace are the U.S. audience, which is tried and true when it comes to being susceptible to ads.

If the game designer produces more content than he can consume per month, some fraction of the people will say more quests, more tests, more challenges, more whatever, and they will be compelled by it.

The single most important top-level trend is the shift to mobile.

We're all put on Earth for a limited amount of time. Am I using in a way that is great, or good enough, or wasteful?