* Emphasise headings
* Allow users to skip past header sections automatically
* Ignore information unrelated to the content (aside sections)
* Allow users to navigate by heading structure
* Voice certain parts differently - links are an obvious candidate, but screen readers could put on different voices for quotes
* Etc etc etc.
Semantic web is suppose to elicit meaning from content, not presentation.
The whole concept of semantic markup is extremely fishy to me. On the one hand you're supposed to remove presentation directions but on the other it's supposed to give presentation clues to screen readers?
Think of screen readers as having internal styling. Links are read in a different voice because the screen reader is applying a default audio style to the page.
Audio styling is part of CSS2.1 [1] but isn’t widely supported or widely written (classic chicken/egg problem). If you want to you can (at least theoretically) over-ride a screen reader’s default presentation of your markup.
If usability is the only answer and it's doing precisely the opposite of what semantic HTML is supposed to achieve, namely separation of content and presentation, it appears to me that we've not really decided what semantic HTML is, it just sounds kinda cool and has a happy side effect of making it easier for screen readers to parse.
So many of these new tags seem too narrow, a victim of the old fashioned thinking of the w3c where everything, to them, is still a document.
Why use article instead of div? Will it really make mining easier or will you get loads of false positives? If my site creates hourly weather reports, are they articles? Why can't I define my own tag of weatherreport? Is there any point?
To quote ryan's original comment:
This isn't 'bringing the web forward' in any sense. I don't know what the answer is but it certainly isn't this.
It would seem to me that decentralized, ad-hoc microformat micro-standards would make more sense than a slow, bureaucratic process. The web will adopt good ideas, useful semantics, etc., so I don't really see the benefit of a 5+ year process of introducing a few new tags.