So if you don't want to spend 2 hours re re re reinstalling for nothing, here's the scoop:
After rebooting your Mac, the win7 bootloader will show the animated win7 logo, then the screen will turn blank.
That's because the driver for your ATI video card on win7 64 isn't compatible with Mobile Radeon 4xxx, so just pop the win7 cd (or boot in safe mode) and delete the following file:
That's a lot of thanks to the PCWorld writers from me then. Here's the step by step guide to installing win7 64 on an iMac from pcworld.
Cheers then!Yeah, I got a 27'' i7 Jumbotron and I can't stop drooling. I'm a fanboy, there. At least I can pretend it's for running BSD :D