Hal Varian: Regarding the Economic Impact of the Web.

Hal Varian is one of the smartest people to ever think about the web.  He's also the author of one of the best books on the subject of the networked economy.  Varian is an economics professor at Berkely and, a couple of years ago, took the job of chief economist at Google. 

Recently, he was interviewed by McKinsey and the video is well worth your time.  Here's a snippet from the transcript: 

We have to look at today’s economy and say, “What is it that’s really scarce in the Internet economy?” And the answer is attention. [Psychologist] Herb Simon recognized this many years ago. He said, “A wealth of information creates a poverty of attention.” So being able to capture someone’s attention at the right time is a very valuable asset. And Google really has built an entire business around this, because we’re capturing your attention when you’re doing a search for something you’re interested in. That’s the ideal time to show you an advertisement for a product that may be related or complimentary to what your search is all about.

Highly recommended.  Here's the link to the interview.