I had a go at rewriting the Blocks code without using tables for layout. I'm quite pleased with the results and would like to get it into 1.5 if possible. To that end I would appreciate folks giving it a try and reporting any problems/suggestions.
I've attached a zip file with a replacement for the current blocks
directory (remember to back up the old one) with an updated superclass for the block infrastructure and a few of the individual blocks have been subtly rewritten too, in order to minimise unneccassary tables.