There's something extremely boring about a web paradigm that doesn't include my toilet taking medical stats to send to my health specialist etc.

One man's utopia is another's Orwellian nightmare.

This is all a bit off-topic Steven. I don't know whether Ian Hickson is right or wrong about the semantic web, and about teaching new tricks to humans versus computers. I do care about whether HTML5 is going to support important accessibility features. Whether HTML5 should play a large role in the web's future or not, I think it is likely that it will. So it needs to be accessible and it needs to support existing adaptive technologies. Faulkner, Clark, Lemon and Edwards are all right that there is a problem here and the hardest part seems to be conveying it to the authors of the specification.

most people wouldn't know how to code all of that semantic stuff so it shouldn't be there, why worry about it and we'll just dumb down our ambitions (eg. Flickr users case study and alt attributes may come to mind in HTML 5)

Semantics are extremely important to a rich and accessible web. I'm not sure whether XHTML is the best way to achieve that richness, but it seems fairly clear that XHTML as XML is not really working out the way the W3C planned. The big question is what to do with that. Regarding alt, it's pretty clear that I'm in favour of requiring it.