I see this thread is two months old without any replies, but I found it while doing a Google search about something similar. Just curious if there was any resolution, because I've run into something with my 2.6GHz 17" high-res MBP where the right palm rest creaks with any change in pressure or position of my wrist while typing. It's barely audible when the machine is cold, but it gets louder as the machine warms up.
Since I type a lot, all day long and in a quiet environment, it's sort of a leaky faucet. No big deal at first, but once noticed it becomes progressively more annoying until you can't stand it anymore.
I'm taking mine in tomorrow and betting a replacement of the top case will fix the issue. I'm happy to say that my local Apple store has always been EXTREMELY good about customer service and satisfaction, even when it means breaking with some of Apple's more annoying points of policy, so I'm fairly confident they'll be willing to work with me on this and replace the top case under warranty, even for such a minor "defect".