I like this snippet from his recent CNet News.com Interview
"We, with our Office franchise, are committed to making workers far, far more productive than they are today. And believe me, we're not running out of ideas. The phone is inefficient today with phone tag and busy signals. E-mail is inefficient today with seeing stuff that's less relevant and how you organize it--bringing in the blog-type capabilities is very important there.
There's plenty of room to do dramatic horizontal innovation that will drive productivity in every sector of the economy. Whether it's scientific discovery, health care, engineering, marketing, sales--you name it--the tools around Windows and Office are not even half of what they will be. "
Many people think that Office is too mature and full of too many features. But I agree the notion that we have much much more to do. Helping people be more productive is a key challenge that Microsoft is committed to.