I just installed Windows 7 on the boot camp partition on my old Powermac G5 running 10.5.8.
I started by using the boot camp assistant (I think version 2.0) to repartition the drive. I then tried to use rEFIt to install Win7 on the boot camp partition from a USB drive, but that didn't work. So I booted back into OS X to finish the process with boot camp assistant and use a Win7 DVD to do the installation. Everything went smoothly and Win7 is up and running.
However, if I hold option to start and choose the Mac partition, nothing loads--it's just the Apple logo and a spinning wheel (waited 20 minutes at longest). Did I make a mistake not uninstalling rEFIt before installing win7 to bootcamp? I haven't installed the apple drivers in Win7 yet--does that have anything to do with it? I reset the nvram/pram, tried booting into safe mode by holding shift (didn't work), tried to get disk utility to show up with the command + R (nothing happened), and then tried a OS X disc 1 disc to boot from, but as soon as it booted, it told me I had to restart (same thing 3 times).