The Register has a hilarious list of reader-contributed definitions of Web 2.0, which is the current buzz phrase for a whole new deluge of technology "solutions" in search of a problem. Web 2.0 offerings typically include other buzzphrases like "live" applications (apparently everything we've been doing has been dead), AJAX (not a soap, but a new set of programming tools), and the always delightful but overused "usercentric."
While Web-based applications have improved dramatically over the past several years, there is unquestionably another whole group of "Web 2.0" start up companies with often baffling offerings that manage to be simultaneously just plain amusing and incomprehensible at the same time. A site called TechCrunch provides a nice snapshot. Most of the stuff just leaves me shaking my head while humming Prince's "Let's party like it's 1999."