The company [Microsoft] really has to chart a direction in mobile devices. Because if you're going to be mobile-first, cloud-first you really do need to have a sense of what you're doing in mobile devices. I had put the company on a path. The board as I was leaving took the company on a path by buying Nokia, they kind of went ahead with that after I told them I was going to go. The company, between me and the board, had taken that sort of view. Satya, he's certainly changed that. He needs to have a clear path forward. But I'm sure he'll get there.

In terms of the public positioning of the company, Satya's [Nadella] done a very good job. He sort of pivoted in a way that I don't think would have been possible for me to do even if I'd seen it that way, to really talk about this mobile-first, cloud-first world.

If you look at companies with upside potential, Twitter's right there. They've established a brand in a world where it's extremely difficult to establish a brand. It's a global brand, people recognize it, people want to let you know what their Twitter handles are, etc.

Computer science is the operating system for all innovation.

I'd rather use Windows and Internet Explorer in Hell than I'd use Linux and Mozilla Firefox in Heaven!

Accessible design is good design.

We'll get a chance to go through this [Apple versus Microsoft debate] again in phones and music players. There's no chance that the iPhone is going to get any significant market share. No chance. It's a $500 subsidized item. They may make a lot of money. But if you actually take a look at the 1.3 billion phones that get sold, I'd prefer to have our software in 60% or 70% or 80% of them, than I would to have 2% or 3%, which is what Apple might get.