i really don't have a prefferance.
my main computer is my uniwill with an AMD64 3200+. It works, less heat than a P4, the 64 bit is very nice, and overall its a very stable chip.
my secondary laptop, the thinkpad with a P3 1.133ghz also just works and gets the job done. not very hot, and the battery life is around 3.5 - 4 hours, not bad.
my bro's lappy is Asus Z71v w/ Dothan 1.86. I dont get to use it much, but today i noticed heavy lag while scanning with Spybot and trying to do other things. granted its a mobile chip, its not really for power users. but overall the job gets done eventually.
-st- i guess what i am trying to say is well....a CPU is not something that really makes a differance. its just a chip deep inside the laptop that makes the thing run, sure there are slight differances in speed and behavior, but at the end of the day, just doing every day tasks you won't see it. the brand also doesn't matter, because people just dont care if you have an "Intel Inside" or "AMD" sticker on your laptop (i have none....not because i ripped it off, but because i never got one...only have an ATi sticker).