I think we agree on quite a lot of this. The unfortunate (from my PoV) part of Google’s attitude (which I don’t blame them for) is that Google is able to define ‘commonly supported’. So, they introduce something like ‘Google Sitemap’, and loads of people start using it. They aren’t a neutral party.

An announcement from Google that they were going to explicitly use hCard etc. along the lines of the recent Yahoo announcement would change people’s attitude to it – suddenly everyone would want their data available in that format.

I suspect the problem with structure is that in order for it to be meaningful we have to all agree on the same structure – since this is the hard bit, it’s much easier to use things that have got some agreement round them (like RSS or Microformats) than it is to hammer out something new. I’m all for this, and would love to see us adopting these as standards on the web for MLAs – but lets think of them as a basecamp rather than the summit.