Many wonderful cool startups in that area..

Just at the top of my head, some of the popular ones:

http://www.trueknowledge.com/
http://www.twine.com/
http://www.metaweb.com/
http://ontos.ch/
http://www.systemone.at/
http://www.powerset.com/

and so on and so on. Web 3.0 hurray..

The topic is interesting because of the shift mobile media usage is bringing (from push to pull to query) and because.. it's most a most nerdy topic that is currently profiting hugely from involving more of those .. interface folks :)
And because there's something going on in Europe.

I'd help organizing a session or giving input in any other way, if need be.

Some Videos: http://del.icio.us/hannes/video+semweb

Cheers,
Hannes