Great feedback! One of the major reasons I asked is the potential issue of heat. In numerous tests I've performed between 5400 & 7200 rpm laptop drives in the PC space, I've noticed that surprisingly some of them offer only a small speed increase. That said, other 7200rpm drives have demonstrated a very beneficial speed increase. The same goes for the heat issue. Some run warm, others not so much. Since the MacBook Pro does not have large ventilation slots on the side or rear of the computer, my first concern was with potential heat issues. In addition, recently I read a review of a mid-2009 MacBook Pro 2.66 / 4GB / 320GB @ 5400. They were very impressed with the speed of the 5400 as compared to other 5400's they had tested. Finally, last night I was at the genius bar, at my local Apple store. When I asked them, they suggested the 5400, which truly surprised me. Especially since I put the emphasis on speed. So it was taking those things into consideration that caused me to ask about it.
I'd try an SSD, but since its a very expensive option, and not easily user replaceable without voiding my Apple Care warranty, I will wait till prices come down and capacity rises.
Since I've always preferred a 7200 rpm drive, I'm going to stay with that choice as I go forward with my MacBook Pro purchases.