Joe McKendrick at ZDNet cites Joel Spolsky and his "Web 2.0" rant.
What is particularly interesting about this new hype-term that this is the first technology term that describes nothing at all about technology. It rather seems to describe that a suffiently large, critical mass of people has grasped a sufficiently broad set of technologies (most of which have been available for the past 4-5 years) for DHTML and XML to actually go mainstream. And clearly contributing to that is (even though everybody seems to complain mostly about IE and its gaps in standards support) that Mozilla seems to have managed to clear the dreaded Netscape 4 garbage off the net.
AJAX is the same buzzword b/s. I am currently building an AJAX app, yay! In order to remember a few things and how they worked, I dug in code dating a few years back that sits in my "OldStuff" directory. Innovation!
And VCs going crazy about this is something that absolutely shocks me.