MBP temperature questions...

just 2 quick questions. Ive searched the forums a bit, and while Ive found hints, i cant quite answer my own question.

First, my macbook pro 2.6ghz (Merom proc) can run as hot as 165-170 degrees Fahrenheit while surfing the web/streaming videos. This seems a bit hot to me... I realize these computers tend to run pretty warm, and as i slow down net usage and the computer idles more, the temp drops as low as 120 F, but usually hovers (with casual use) between 140-150 F. I've heard of some macbook pros running much MUCH cooler, as low as 100 F. These might be older models though, with considerably slower processors.

Second, how does apple handle heat-related issues? Ive heard of people replacing the thermal paste (I'm VERY reluctant to do this myself)... is this the sort of thing apple maintenance would do? Or will they just send me on my way and tell me its normal.

I don't use my laptop ON my lap ever, but i worry about the machine overheating, and the kind of damage this can do to the processor or the internal circuitry... at what temp should i REALLY begin to worry that my processor is pushing it too far...

Thanks
Chris