If you have a bunch of full time designers on staff let them toy with CSS all day long to get the right layout. Otherwise take the PG approach and treat HTML as object code.
A better (serious) solution would be to transform the layout based on the user agent. For IE generate tables, for any other UA generate divs with the appropriate CSS using display:table. Everyone is happy!
Okay, seriously, here's my question to startup website developers. Is it wise for us to spend significant time trying to avoid using tables in our often-changing layouts, in the hope that a blind user may have a slightly less confusing experience? I'm not quite going to say YAGNI, but I will say I'm not convinced.
If you're serious about accessibility, good for you -- use VoiceOver or JAWS, truly check your site out. It's a lot more laudable a goal than having your HTML perfectly pass some XHTML validator. Otherwise, I think it's one of those things we can sensibly put on hold until after our B rounds.