To me there is very little confusion about why people are spending their time and energy to get Windows to run on Apple hardware. Put simply, they are doing it because it hasn't been done before. Let's say someone manages a sloppy hack and gets Vista to run. A month later someone will still be working to make the process easier and more "novice friendly". You work at it for days and weeks at a time because it is challenging. If, after you're done, someone uses your discovery to run Outlook on an iMac, so be it. For most this is not the primary motivation.
For some people, simply standing in awe of a majestic mountain is thrilling enough; others are compelled to climb.
Here's to getting Pro/E on a PowerMac by 2007!!