Why would he go through the trouble? This is exactly what running the XP Setup in Virtual PC looks like.
And since the G5 iMac and the Intel iMac look the same from the front, it could just be a G5 iMac running Virtual PC.
Heck, and you read it first here, I'm in the process of hacking up a video that will be 100% believable of running XP on my MacBook Pro. At least on there, it will look legit. How will I do it? Using the video out function on my PC, and a camcorder with video in, I'll record XP booting, and doing some tasks like starting up notepad and typing something. Then I'll play the video back on the MacBook Pro full screen. I'll record this on my digital still camera's 'low quailty movie mode' (claiming it's the only movie camera I have,) and because the camera will be far enough away from the MBP to 'verify' that it is indeed an MBP, you won't be able to tell that it's just a movie playing at 640x480, it will look just fine. And to complete the illusion, I'll have the MBP 'off' when starting playback (on battery long enough that the backlight turned off,) and will hit the power button to turn it on. In reality, I'll be hitting spacebar on a wireless keyboard to start the video playing. I'll have the internal trackpad disabled, and match the movements of the Windows mouse to load up an app. Finally, typing on the MBP's keyboard to match my typing on the Windows video... (Just have to be careful to not actually hit spacebar.)
Now, I've posted the fact that I'm going to do this, and posted exactly HOW I'm going to do it. When a video of an MBP running Windows magically appears on the 'net, will anyone call me on it? I bet it'll make Slashdot. (Of course, I'll be hosting the video on my .Mac account, so it will go down quickly, fueling the rumors.)
I have already recorded the Windows part, I just need to practice the timing of mousing and typing so that my fake typing on the Mac matches the typing on the Windows machine.