From a music discussion on the Freakonomics blog...very interesting (and true):

The majors thrived in an era of artificial scarcity when they were able to control the production and distribution of music. Today, we have an infinite number of choices available to us, and when content is infinitely abundant, the only scarce commodities are convenience, taste, and trust. The music companies that are successfully shaping the Internet era are recognizing that the real value is in making it easier to buy music than to steal it, helping consumers find other people who share their music tastes, and serving as a trusted source for discovering new music.