If anyone has had their laptop for a while now, and they are experiencing any overheating issues, I definitely recommend opening up the heatsink and cleaning it out. I've had my 5660 for over a year now, and I'm usually pretty careful about where I place it, but when I opened that sucker up (the heatsink), I found that more than 90% of the ventilation was blocked by dust!!!
So maybe thats
why my laptop was idling at 61 ~ 63 degrees (well, I guess I could mention something about the fake silver thermal compound from CompUSA, but I'm too embarassed to get into that). The cover of the heatsink on the 5660 is held on by 3 small screws and 4 small latches. The only screwdriver that I found to be small enough to work was one for repairing eyeglasses, which I also used to pop off the cover from the latches. Then used a vaccum and some alcohol soaked q-tips to remove as much dust as possible (remeber to not let the fans spin when vacuuming!). After putting everything back together, and replacing CompUSA's garbage with Arctic Silver 5, my laptop now idles between 40 ~ 47 degress. Soooooooooo much better.
I actually ended up getting scared when I was in bed later that night when the fans turned off. I thought my laptop had died until the faint clicking of the hard drive reassured me it was still alive and kicking. I can't remember a time when the fans have ever been off except within the first 10 minutes or so from bootup.