Unity iPhone is a specific, additional-cost Unity option that automatically connects with Apple's Mac-only Xcode tools. It will not run on PC. However, the regular Unity (for making Mac, Windows and Web games) does run on PC and has some degree of compatibility with Unity iPhone. So you could at least START a project on PC, but you'll need a Mac at some point.
The last thing Apple needs is more iPhone developers.... But they do like to sell Macs, so they have no motivation to do as you suggest. --Eric
