I'm sure I'm not saying anything new but I wanted to get this down.
I've been separating out the concept of content syndication from the semantic web, but that is a mistake. Weblog content syndication, which is the technological force that has powered the current wave of online Progressive activism, is the original semantic web application. An RSS file is a collection of metadata that points to people's posts. That metadata is combined with tools allowing people to easily discover and distribute information.
While the "blogs" get all the credit for what's been going on, it wouldn't be anything without the semantic web as the conceptual distribution mechanism. Take away the semantic web and all you'd be left with is bulletin boards, which we've had for a long time.
The semantic web as a concept has taken a lot of hits for being unworkable. What's already been done online with political activism is proof positive that it isn't.
In the end the real difficulty is with making the RDF specification something that can easily interact with content in various formats. The solution by makers of blog software has been to not use RDF and create specs that focus entirely on the 1 dimensional streams that are blogs.
The future has got to be with breaking away from this 1-D prison.