If it's OSX you want to run (and why shouldn't you? ;-)) I agree with the statement of getting a decent IntelMAC. No issues on the OS side of things and, with BootCAMP, legal installation of WindowsXP (don't know about Vista) is still possible. And Linuxes should be no problem either. What might be a reason not to do it is 3D performance. But then.... Guess the ATI and nVidia options in the different iMacs should be good enought.
