Judging by Josh Catone's post and its comments
There is No Web 3.0, There is No Web 2.0 - There is Just the Web, people really don't like the terms "Web 2.0", "Web 3.0", and the like. But I'm not sure I fully understand why.

If it's because people have a natural aversion to labeling anything, I can somewhat agree with that. Determining the definitive characteristics and exact point of inception of a fluid event like the evolution of the Web into "Web 2.0" is difficult. Being hesitant about focusing too much on nomenclature and not enough on application is also somewhat valid. The more time spent arguing about what the web is, the less time building applications for it.

But ironically in avoiding or vehemently opposing labels such as "Web 2.0" in order to focus one's effort on producing real output, one may become less efficient and effective because he or she has unwittingly denied that there wasn't a drastic shift with the internet as we know it. And by not recognizing pertinent aspects of the current web and its shift from previous incarnations, one is less apt to deal with the next major shift. And there is definitely going to be another big change in the internet and its use, most likely pretty soon - that has to be taken as a given at this point. And by studying the web today, which I think can be correctly named "Web 2.0", and its variance from the initial incarnation of the web, there are some key lessons to be learned.

First, increased bandwidth opens doors. When we were all using dialup, static html pages were all we could handle. I can definitely recall visiting huge pages on my family's 500 series Mac via AOL dialup and completely crashing my Netscape browser. The kind of interactivity available today just wasn't possible with yesterday's internet. Today around 3/4 of the country has broadband internet access so sites are able to deliver that much more data to the user and not have it take 3 hours. This completely changed the UI philosophy of the web and today the intricacy of the average user experience is exponentially greater. Now with that in mind, if the average internet speed jumped from 1MB/s to 10MB/s, what would that mean for the actually look and feel of the internet? Something pretty drastic right? Imagine an experience like the one seen in this recent TED talk.

Secondly, massive amounts of data have completely changed the way we consume information. I haven't opened an encyclopedia since College (ordering OED Compact Edition soon however). Web 2.0, despite a few niche mashups, is mostly about the quantity of information. And now that the amount is there, I definitely think Web 3.0 will be about integrating these stores of data even more intricately. Not just simple mashups, but gigantic, intelligent search engines and maybe even *gasps* the beginnings of true artificial intelligence.

Finally, there's a (somewhat shocking) move towards openness going on. In the first iteration of the web personal outlets were somewhat minimal. We had chat rooms and personal web pages - mine was on Tripod and was a Gators fan site. Web 2.0 has brought us, of course, social networks and the importance of building "networks". I think Web 3.0 will involve the creation of complete online personas, distributable everywhere. This ties in to the sharing of information touched on in point 2, but on a more personal level. It will involve sharing personal information, social data, favorite pieces of web content - basically everything you do that involves the web - on all the sites you visit. Clearly this'll bring up questions of privacy, safety, etc. but it seems to be the way the web is moving.

Obviously there will be other changes than the ones listed here, but I think these will be drastic enough that the web will look totally different from the web of today. And when something evolves out of something else, taking on different characteristics and unique features, we generally label it as something other than the former. In this case, the label will be "Web 3.0"

In Conclusion,

I CAN'T WAIT!