Apple's choice of processors may depend on how dramatically it redesigns the MacBook Pro next year. Rumors have persisted that Apple is working on ultra-thin models that may represent a complete overhaul of some of the MacBook Pro models, making them more Air-like in design.
There are lots of rumblings that Apple will kill the optical drive in its 13" and 15" MacBook Pro line. It seems the 17" will still keep the drive to satisfy the few hardcore production people who for some reason still work with DVDs (not Bluray, mind you). The question becomes, well what do you do with all that real estate now that an optical drive is no longer there. There have been rumors of an ultra-thin Air-like 15" MacBook (Pro or Air?).
If it were up to me, I'd stay away from thinner. Maybe a little thinner is ok but don't try to create a 15" MacBook Air. As a previous Air owner, I loved the sleek design and super light machine. However, I found myself growing tired of how under-powered it was and the constant high whirring of the fan when I did more CPU intensive activities. I eventually switched to a 13" MacBook Pro and thought it was a great compromise between power, performance and size. So I would hate for them to kill the 13" MacBook Pro in favor of sleeker underpowered (relatively speaking) machines. Instead, take the empty real estate and either add more storage, RAM, or better yet more batteries. At the very least, just take out the drive so it's slightly lighter but don't trade sleek for power when the 13" MacBook Pro is already pretty sleek.