What is Web 3.0?

Kent commented on my Ubiquity post, saying perhaps it (Ubiquity) should be called a Web 3.0 tool.
I replied asking him what he thought the Web 3.0 would be like.

Now, I don't know if he'd read something along these lines but I stumbled onto something today...

Click.

It's an old article, but what do you think of the idea of a semantic web?