I think that Microsoft will increasingly feel margin pressure from Linux as well as people saying: well actually the applications that really matter to me are not on my PC. And so they're going to be able to extract less of a monopoly rent, so to speak.

I think that companies always become complacent, over time. Or most companies, that is.

When you have to prove the value of your ideas by persuading other people to pay for them, it clears out an awful lot of woolly thinking.

I think Microsoft will have to change. I think that the business of Microsoft, the company of Microsoft, is going to continue to succeed. But I think the business model of Microsoft is going to have to change.

The biggest mistake we see companies make when they first hit Twitter is to think about it as a channel to push out information.

Collective intelligence. Think of how Wikipedia works, how Amazon harnesses user annotation on its site, the way photo-sharing sites like Flickr are bleeding out into other applications... We're entering an era in which software learns from its users and all of the users are connected.