I have just reread Paul Graham's piece on Web 2.0 which has some nice things in it, including:

But there is a common thread. Web 2.0 means using the web the way it's meant to be used. The "trends" we're seeing now are simply the inherent nature of the web emerging from under the broken models that got imposed on it during the Bubble. [Web 2.0]

This thought is echoed in the opening entry in Tim Berners-Lee's new blog.

Timbl's blog via Peter Brantley and, incidentally, is linked from the entry on him in Wikipedia.