Unfortunately, for the time being, it's x86 which means that wherever Intel's Pentium is in a year or two, that's where Apple will be. And as much as I dislike that, it's actually a pretty good first step. By first going with x86, it insures that Apple will always have a steady supply of fast chips. Regardless of what else is out there in the market. I expect that once this transition is made, they'll be free to branch out however they deem fit.
Also, ArsTechnica has a pretty good
writeup about this, if anyone's interested.