Apple needs to make this happen. They're going to fall behind if they don't.
OF course, there's probably nothing stopping Apple from helping Oculus add support. Whether or not the video output from current iOS devices would be sufficient is another question, but then the same can probably be said for any kind of random Android hardware. In terms of software, I'm pretty sure Apple could add whatever is needed- hell, we even finally got official game controller support, anything is possible
Initially, I think PCs are going to be where the Rift stuff really shines for now, since GPUs are just so many times more powerful on the desktop.