I had upgraded to Lion on my 2.2 2011 MBP 13 inch and I noticed that I thought it was running warmer than before. I used Istat pro. With Lion, running Chrome browser, with about 15 tabs, and just doing light forum reading, my CPU was around 120-125 F and my base was around 90F. Fan was running around a constant 2000 rpm.This was after about 45 minutes from a shutdown unit. I removed my HD and put in my original SL hard drive and ran the same test. The temps were just about the same. SL might be running 2-3 degrees cooler, but that's it. End of experiment. I am going back to Lion and just live with it. It seems like the only real way to cool down the unit is to run a fan control app and program it differently than the OEM fan program. Or maybe I should just drill big holes in the bottom of the case. Looks like we have a normal MBP, but they just run warm.