"I figured out a way to get into the EFI menu on the new Intel iMac. I was attempting to install Vista, which did not work. As I discovered from poking around in the EFI there is no support for UDF or El Torito volumes. It seems only GPT and APM is supported. Writing a driver for EFI to support UDF should be easy enough for someone who knows how, one might even exist already. I'm going to give step-by-step instructions for getting in to the EFI so that some enterprising people will get to work on installing Windows."