Web 2.0

Web 2.0, is an architecture of participation that links between web applications, blog publishing and self-service advertising.
This architecture is based on social software where users generate content, and an open programming interface.

Blogs democratized publishing, now "tags" could be considered to democratize information architecture. What's behind this? Are powerful tools in the hands of millions really better than well-trained experts?
http://www.kottke.org/04/10/design-for-web-20