I've gotten in just enough "what is Web 3.0?" conversations to appreciate this definition (via Web 2.0 Journal):
Defining Web 3.0
The defining aspects of the Web 3.0 social experience may therefore be as follows:
· One, that you won’t need to “go” anywhere, except maybe to set up some initial parameters. Where your computer is, is where you are. Information comes to you based on tags and search criteria; you don’t have to go out there.
· Two, that there are no pages. Information comes in packets of discrete units. You merge or cross them, as you need to.
· Three, that there are no Web sites. Existing Web sites are no longer meant for human eyes. They act as indexes to the information, which is accessible via XML request. Exceptions to this will not be Web sites, but independent little islands of commerce or games.
· Four, that creating information is like writing an email or writing a document. Accessible to anyone with a computer.
· Finally, that being on the Web means not being on the Web at all. It is like being “on the telephone”, i.e. you have a telephone in your house.
I believe that some of these can be and should be part of current Web 2.0 design but the line between Web 1.0 and Web 2.0 was blurry (e.g., eBay) so why should it surprise us that the transition to 3.0 won't be as grey?