Which Website Markup Language?

Dear Lazyweb,

now that I've finished my Ph.D. thesis (i.e. now that I'm officially unemployed :-) ) it's time to renew my vetust homepage. That page is written with WML, I used to be quite happy with it, but this is no longer the case (lots of reasons for that snippet).

I'm now looking for an XML based markup language for re-writing my new homepage, the features I would like to see in a tools based on it are:

  • content-oriented XML-based markup for describing the content of the website (if not XML-based at least processable via an API implemented in some programming language I like: python, ruby, ML, ...)

  • legacy XSLT (or whatever if not XML-based) transformations for generating XHTML 1.1 pages which can be statically served by a web server requiring no particular extensions

  • ability to extend both the input format of the transformation tool (e.g. adding support for new XML dialects) and the corresponding transformations, and to integrate the results in the resulting website. Relegating the results of the ad-hoc transformations in a subdirectory of the resulting website which is not integrated elsewhere is not ok

  • ability to integrate verbatim snippets of XHTML/Javascript/... in the input document where needed (hopefully not so often)

  • clean final XHTML pages which rely only on CSS for presentational purposes would be nice

  • support for predefined common website layouts would be nice (e.g. 2/3-column layouts supported by Google Page Creator)

Of course I can design my own XML format and all the needed XSLT transformations, but I would like to avoid re-inventing the wheel if possible.

Actually a while ago I think I read about a couple of tools like the one I'm looking for here on planet, but right now I'm unable to find the relevant posts. Similarly I'm apparently unable to find the right set of Google keywords for finding anything useful.