Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.
My 2007 MacBook Pro easily reaches 500 F when using Windows 7 via bootcamp. At least, that what my legs and wrists tell me.
 
At its worst running iTunes and Flash video, my Macbook Air 11"inch barely ever gets warmer than lukewarm.

My old mid-2009 MB Pro, used to get quite hot, but never as hot as the crappy HP/Dell PCs I used use before I turned to the Mac-side.
 
^The dual cores and higher strain put on the computers is going to warrant the higher temperatures.

Mine has gotten to 91 C once... about two weeks ago I was playing a game and had some other things going on in the background and smelled something burning; something on the inside of the Mac had I guess been burnt.

I ended up turning it off and going to bed... it was a little too late anyway ;)
 
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.