You can run anything as long as it is OS X
Dave Winer is reporting some juicy details about Apple's recent Intel announcement, '1. Apple is not going into the software business, their operating system will not run on other vendor's hardware. So you won't be running the Mac OS on Dell, HP or IBM, for example. and 2. While Windows is not explicitly supported, they won't do anything to prevent Windows from running on their hardware'
The world is just getting more and more interesting, isn't it?