I have hand-coded from scratch a concept demo of the phase IV new dynamic layout I'm thinking of. This should be XHTML 1.1/CSS compatible.
http://www22.brinkster.com/rotemdan/phase4-concept-demo.htm
NOTE: please view with Mozilla (tested on 1.4), IE doesn't display the widths correctly (though it does work somehow) and the transperant logo. I haven't had the time to tweak it for IE yet.
Regards, Rotem