Will Apple Switch the Mac to ARM? Why Rumors Do, and Don't, Ring True. - Arik Hesseldahl - News - AllThingsD

Will Apple Switch the Mac to ARM? Why Rumors Do, and Don't, Ring True. - Arik Hesseldahl - News - AllThingsD: "Apple’s last shift in chip technology happened during 2005 and 2006, when it pivoted away from the old IBM-made PowerPC architecture and instead embraced Intel’s processors, which already run inside most of the world’s personal computers."

I think this would be a relatively easy transition except for the emulation layer.