Not much difference these days. The Core 2 arc h i tecture fixed that, the last Intel furnaces were the Prescotts and Pentium-D's.

EDIT: Isn't this going a bit too far adding c h i t to the word censor?

 

Biggest problem heat wise between the AMD/Intel, at least in the past, is that if the Intel gets too hot, it just slows down. If the AMD gets too hot, it fries the processor and the MB. Saw pictures of when they removed the fans and did tests. The AMD melted everything, while the Intel, once the properly cooled it went right back to working normally.

 

That's also ancient history. AMD now has a proper motherboard-based overheat shutdown.