Tim O'Reilly on Web 2.0 and TWiT.tv podcast on mashups

What Is Web 2.0 by Tim O'Reilly
Article: Design Patterns and Business Models for the Next Generation of Software (5 pages).

Inside the Net 13: Web Mashups on TWiT.tv
Podcast: Takes a look at one of the coolest new phenomena to hit the net: web mashups (32 minutes).