What a tangent, but if you want to go down this rat-hole, whatever. I know what avengineer said, but things have changed dramatically since then. In the scenario he was referring to, Apple was confronting a situation with their PowerPC CPUs where they would be offering premium pricing with noticeably inferior performance. Intel's CPUs were so much faster than what Apple had that the apps ran as fast or faster on an emulator on Intel's CPUs as they did native. I'm sure the last thing Apple wanted to do at the time was pay Intel's premium pricing. I mean, who does Intel think they are? Apple?
Beating Intel on its own turf, laptop CPUs, in premium products probably isn't going to happen, now that Haswell has world-class power management and the integrated graphics Apple needs for even Retina displays. Intel is probably two fab process generations ahead of anyone else, so even if you think their design capabilities leave something to be desired, or that x86 architecture is somehow inherently hobbled, the industry's only production FinFETs will probably make up for any shortcomings in the Air market.
Thunderbolt is an Intel-proprietary technology. It's not an open specification like USB or PCI. Only Intel makes the chips that support it. Why would they give that up so that Apple could go to ARM easily, and lose billions of dollars in i5 and i7 CPU business? Maybe, but I'd bet against it. What would they have to lose, if they lost Apple's laptop CPU business?
iOS products are a different question, and an interesting one. I'm a doubter that Intel will get the iPhone CPU business. iPads already go for a day without recharging, and maybe I'm just a dinosaur who doesn't play the right games, but I'm not seeing an iPad performance play for Intel either. But, you never know, Intel won the Samsung tablet with Atom, and those two companies are not exactly the best of friends.
There is an argument that says that companies that spend the majority of their resources innovating on their current products are less likely to do the really new next thing. On second thought, maybe I wouldn't be so surprised if Apple decided to put the legacy products, like iPhone and iPad, on Intel, just to free up a bunch of their best resources for whatever is next. That's what a really innovative company would do, IMO.