I'm still using the PowerBook G4 I purchased in 2004 daily. I'm typing on it right now. And I'll echo the claim that resale value on a Mac machine are generally insane compared to what you would get for a comparable PC. (To cite one instance, I sold my 2 year old 20" iMac G5 AFTER they had released the intel lineup, and still got almost a grand for it... over 2/3 of my original purchase price.)
I recently purchased my girlfriend a MacBook for school. She absolutely loves it and hasn't had a single problem with it (yet... knock on wood).
As for MacBook Pros, pretty much everyone I know in my industry owns one. If they don't it's only because they can't justify replacing their PowerBook yet, since it's still going strong.
Penryn chips appear to have alleviated, if not solved, the heat issue. So now would be the time to get a MacBook Pro if you were holding out. Additionally, if you're debating between MacBook and MacBook Pro because of the footprint, trust me when I say there is not a huge difference between the two. That is, a 13.3" screen and a 15" screen make the sizes of the two laptops comparable. Now, there is a significant difference between my 12" PowerBook and a 15" MacBook, but that's apples and oranges.
It comes down to your own experience with both types of computers as to which you should purchase... but it's prudent to remember that while you can put Windows on a Mac, you can't put OSX on a "PC."
Finally, I leave with with a picture of our production office table from the last movie I was on.
EDIT: Oh, I forgot to mention in my post that I am more than willing to pay a slight premium for superior ergonomics. That's why I buy first party controllers instead of madcatz, etc.