One of the interesting rumours floating around the Valley these days is that Apple is on track to merge OS X and iOS and move Mac users over to their ARM based processors and leave Intel. If you follow Apple and know their history, you understand that they are more then capable of doing this. Over the Mac’s existence, Apple has actually moved the Mac OS to three different chips sets and has migrated their core OS from one processor core to the other quite seamlessly.
The reasoning goes that Apple could bring the two operating systems together to run on their own chip sets and save them having to pay Intel for their chips and instead use their own ARM processors to run a single merged OS and UI environment. Although this is a plausible idea and could possibly happen some day, the soon-to-be released updated OS X Mountain Lion suggests that this will not happen any time soon. This new OS, which brings a lot of the greatest features of iOS and many of its apps to Mac OS X actually makes the two operating systems even more alike then they have been. But each OS still serves a purpose and these enhanced cross OS functions makes it possible for both operating systems to co-exist and compliment each other for some time.