Apple officially supports dual booting and installation of Windows XP. It's just in public beta now, but will be standard in the next major OS upgrade (10.5). As a developer, I'm excited about this and as a gamer, I'm f'ing estatic! This may mean I can actually convince my employers to buy a Mac as a work machine for me as well.
Now to bring on the intel Powermacs.
EDIT: Made the title more descriptive and removed my grammar mistake as pointed out by BadFerret.