I have noticed that when I run paralles with vista that my MacBook Pro rapidly gets very hot. Anyone else notice this?
Try getting an application like smcFanControl (freeware.) It does a better job then the default fan management for keeping the temperature down. It allows custom settings for min. fan speeds, and maximum temperature thresholds that it attempts to abide by. You should be careful with it though, don't go setting your fans to 6000RPM all the time or anything... Without it my MBP gets exceptionally hot (I run XP all day at work, programming, building products.. testing.. My RAM, CPU and HDD are always constantly hard at work. smcFanControl does a pretty good job of keeping things at around 60*C or cooler for the most part. Without it, I can easily reach 70*C and higher!) This is on my MacBook Pro Core Duo 1.83Ghz/2GB RAM
I second the smcFanControl for use in general on the MacBookPro. I have it set to kick the fans in early to keep the overall temperatures in the MBP lower. It might give the internal components a marginally longer lifespan. I also have a Vista Ultimate VM in Parallels and it's resource greed keeps those processors working overtime. I've turned off mostly everything graphical in Vista but couldn't have pared off more than 5% CPU load from the default Vista settings.