Web 2.0 is mainly a fad. Using bright, pastel based coloring to create a web movement is irrational. Each site should be designed according to the product or service, and what color schemes help emphasis the information being portrayed.
"Web 2.0" has NOTHING to do with colors at all, it was supposed to be about technology. The term has been grossly distorted and overused and yes, is mostly a fad.
__________________
Web Goddess & Web Standards Evangelist :) - Tables Be Gone !!