People here keep thinking the a CPU chip is the only kind of chip. Open up any Mac and look inside. Count those little black square things that are soldered to the PCB and notice that the non-CPU chips greatly outnumber the CPU chips. If you want to make the device smaller, cheaper and use less power, even if the CPU were zero-size you don't save much. We all know that a Mac's mainboard is many times larger than a CPU.
I'm sure what Apple would like is to be able to greatly reduce the nuber of non-CPU chips. Doing this is the only way to greatly reduce the size of a maniboard. but you can only do that if you have the abilty to do chip-level design.
I think it is clear that Apple knows that a small designer can't really compete with Intel when it comes to CPUs. They did not Buy PA Semi so that they can build better comonity chips, They bought them to design custom lowvolume device specific chips
I think these might find their way into products like the Apple TV or the iPod.