There is nothing -- and I mean absolutely nothing -- unprecedented about Apple's hardware technology. Apple does not lead in hardware adoption, it rather lags the rest of the industry. Apple's true innovation (and this was explicitly the genius of Steve Jobs) is in making existing technology easier for average folk to use.
Sure, Apple is testing out different CPU families. They're no stranger to non-Intel hardware (they were using PowerPC chips up until around 2005 after all), and they've got the advantage of an OS based on BSD Unix, meaning they (at least should) have less trouble porting their OS to new CPUs, unlike other OS manufacturers.
My problem with Apple is not that they are testing OS X on new hardware, but that they have been so incredibly stingy with what hardware they allow OS X to run on. Apple of course limits the operating system to their own machines, but lately they've been putting low-power chips in all their machines, and moreover made those machines almost entirely non-upgradable by the end user.
In short, where the computer industry as a whole has been moving forward with more powerful hardware and into new computing niches, Apple has moved backward, with less powerful hardware and with fewer options.