Ideally, commercial media would consist of equal partnerships between three parties: publishers, the audience, and advertisers. In reality, advertisers, the group with the most money, hold all the cards. Publishers have been relegated to the role of supplicant, and the audience -- well, we pretty much have to swallow whatever deal the publisher and the advertisers cut.

For the most part, the Internet has inherited this model from print publishing: on the Web, there are far more publishers trolling for ad dollars than there are advertisers doling them out. But the Internet's interactivity suggests an alternative economy in which the long-standing imbalance between publisher, audience, and advertiser could be corrected. A system of Internet-based marketing, which I'll call Publisher-Driven Advertising, or PDA, may be soon possible. In this system, publishers would pick and choose from a vast supply of advertisers.