They already have it -- without the fanfare. Apple bought NExT. The NExT technology DOES/DID run on Intel. The hub of Mac OS X is called "Darwin". This is open source and can be installed on Intel, now. (Its Mac OS X without the user interface). The user interface of Mac OS X called "Aqua" right now is ONLY available on Macs. However, the Aqua interface is NExT technology, and it can be ported to Intel with little or no bother.
Everytime Steve Jobs is to make a speech at one of these trade shows, I study at the computer rags for speculation - "Apple's going to announce Aqua for Intel" has been a steady theme- but alas, its just proving to be a rumor. It would sure piss M$ off, as M$ is already objecting to PC manufacturers shipping "naked" PCs (a PC with no OS on it) and are trying to stop this practice. M$ claims that if a person wants a naked PC they're really going to put a bootleg copy of Windows on it. A stupid argument, when there's currently Darwin, Linux, BSD, Solaris ... etc that can be put on the PC...
If Apple were to announce their Mac OS X on Intel, they'd mop up. Let's face it, Apple wrote the book on the human interface with the computer - what ever you think of them as a company, their OS work is right out of the cognitive psychology field when they studied the results of people like Miller et al and devised an OS that really took into account how people react to computer as a system as a whole.
Agreedwithin a few years, they might even take over more than 50% of the desktop market, which would be a phenomenal blow to Microsoft. But they're not going to, because Apple is run by idiots. They guard their dwindling hardware market so zealously that they're perfectly willing to pass up vastly more profitable software salesjust ask anyone who worked at Power Computing. Even if Apple decides to switch to x86 CPUs for Macs, there will still never be a version of OS X that competes with Windows, because Apple will never, ever release a Mac OS that doesn't require you to buy hardware from Cupertino.