Because it's been ported to Mac already, and the iPhone is technically a mini-Mac, I can't imagine getting the code to run would be a big undertaking.
The biggest hurdle I reckon would be utilising the touch and tilt controls effectively. You need the controls to be perfect right from the beginning for the game to be a success on the platform.
Having said that, WOG is a game I'm hanging out for on iPhone. =)
It would be !AWESOME! to capitalize words and put exclamation marks around them. But that's off topic, so I agree.