The Usability Barrier
At the AAAI conference in Boston, Peter Norvig of Google raised a concern about the Semantic Web to Tim Berners-Lee. The concern has primarily to do with ease of use.
We're not going to have a smarter Web until and unless the new tools are easy enough to use. Until then, we'll have Web 2.0, as described here. As Zombini explains, these Web 2.0 technologies already have semantic qualities, but they are held back by "using older, more limited technologies because of our lack of understanding and desire to learn complex new languages."