Think Bash2Cool was one who said he had issues with the Vista Transformation pack messing up XP's settings and ended up having to uninstall it....but I recall someone else saying there were problems even after uninstalling it, XP was not fully restored and a clean install was necessary to regain control....
Seems a bit reminiscent of StyleXP....hacks system files and don't put 'em back. No thanks, Vista RC2 is quite stable and gives me all the Vista-ness I need right now.

BTW, thanks for the info, ID...after reading an article that linked to what were obviously bogus Vista sounds, I've been rather interested in what would eventuate.