plain old xml considered harmful
(This article is a stub, feel free to expand upon it)
The plain old xml approach has already been tried by *numerous* others since 1998 and has failed on the Web.
OTOH, XHTML + semantic class names has seen widespread adoption among the web authoring/design/IA/publishing community. Microformats is leveraging the approach that is both working better and frankly dominating in practice on the Web.
See also namespaces considered harmful.
XML elements are limited to one "name" and thus semantic, whereas the class attribute is a space separated set of names and can thus capture multiple semantics, providing a much more flexible semantic structure for authors, and greatly aiding in following DRY. Note that your example had to
duplicate the "list" semantic with
- and <ia:grocerylist>.
There are 1000s more web authors/developers that write/understand (X)HTML
+ semantic class names + CSS as compared to the number of folks that
write/understand either plain or namespaced XML.
It's the publishers that matter, not the programmers. Or to put it
another way, programmers can solve problems once and share open source.
Publishers have to keep solving markup/publishing problems for content and
design numerous times continuously, and have much less chance of being able
to share their solutions. That plus the fact that there are 1000s more web
designers than programmers plus simple economics means the best solution is
to optimize for ease of publishing, and let iterative open source solve the