SemiAccurate reports that Apple’s transition from the current Intel x86 chips to ARM is a “done deal.”
The short story is that Apple is moving the laptop line, and presumably desktops too, to ARM based chips as soon as possible. With A15/Eagle allowing more than 32-bit memory access, things look up, but it seems silly to do so before the full 64 bit cores come in the following generation. Nvidia is directly telling certain favored analysts that they will have Denver out in Q4 of 2012, maybe Q1/2013, and that uses the full on 64-bit ARM instruction set. It won’t be out by then, but that gives you a good estimation of when that ISA will break cover from one vendor or other. Think mid-2013.
At that point, Apple can move to ARM without worrying about obsoleting code with an ISA that is on the verge of changing, and no memory overhead worries either. Basically, it looks like the perfect time. Ironically, SemiAccurate’s moles tell us that the boys on infinite loop are planning to move laptops to ARM at about that time. Coincidence? Nope.
The advantages of moving to an ARM-based processor are many (battery life, less heat, thinner laptops, could be designed in-house), though skeptics are saying that it is silly of Apple to move to an ARM processor while Intel’s chips are quickly becoming faster and easier on the battery and heat.
As far as the actual operating system, it’s likely that Apple has been keeping Mac OS X compatible with the ARM line of processors for a few years. Such a move was actually done before their transition to Intel chips: for years, Apple had kept a line of OS X working on Intel’s silicon, in case the PowerPC architecture failed to compete with what Intel had to offer. This allowed the transition to be much quicker than it would have otherwise been.
This rumor isn’t as surprising as it sounds: Microsoft announced at CES 2011 that their next version of Windows (referred to only as “Windows 8″ so far) would be compatible with the ARM architecture, in addition to the Intel-based silicon that has previously been used.