4-5 months later and thanks to the whole webdev team pulling together we are beginning to turn the corner into a new era of cleaner, standards based code across the board
We also attempt to keep CSS hacks to an absolute minimum. Should laziness creep in it's tempting to fix rendering differences between browsers with hacks straight away without checking for other reasons why these differences manifest themselves. Should IE 7 fix some of the known bugs but remain susceptible to some of the IE targetted CSS hacks then alot of pages will end-up adrift.
The next stage in the journey is to ensure that all server-side code outputs standards based code, otherwise it will be shame when all the hard work is ruined by a badly written server-side app; a common problem with Content Management Systems.
Overall these changes have come easier than I expected and I am happy to be able to code to my own standards.