NY Times: Web 3.0 is on the horizon. Yes, Web 2.0 is so yester-year and we are eagerly waiting for the latest upgrade.
Web 1.0/Sun: "Network is the computer"
Web 3.0: "World wide web is your database"
Web 2.0: Mesh-up of web-services
Web 3.0: Searching the big mesh-up with warm fuzzy term such as "Artificial Intellegence"
Robert Scoble reckoned it should be called Web 2007, obviously because 2007 > 3.0. They might as well call it "Web Vista". After all, Windows Vista is just an evolved product from Windows XP with a nicer looking shell, marketing PR and lots of hype. So is Web 3.0.
But I guess the market needs it. To prevent bubble from bursting, they need to constantly fuel the fire with hypes and speculations like this. And just ignore nay-sayers like Dave Winer -- there will be plenty of start ups riding on this term to differentiate themselves from the old Web 2.0 crowd.