> people *think* they want, rather than what they'll actually use.  Looking at
> de facto class names is a much better indicator of what new semantics
> authors are actually *using* today.

I suspect that you will find that they use the presentational names
of header and footer, or variations on them.  They are unlikely to use
the more structural names, which I think better reflect the true 
meaning of these constructs on typical commercial pages:  PrimaryBranding
and LegalNecessities.

The branding role of headers, is to me, clearly presentational, and
the use of footers for material that the designer would rather not
have had in the design, is also driven by presentational considerations.

I'd suggest that current subclassing for these represents damage limitation
when seen from a structural point of view.

Incidentally, this thread (that unfortunately I'm getting behind on
responding to) seems to me to overlap a lot with the contents re-ordering
thread on www-style, e.g. copyright notices are re-ordered from the
meta elements in the head element to be in a footer presentational unit.