Why not both? The new Macs can handle both. I have XP and OSX on mine.

Obviously, I have never been able to commit fully to one or the other myself.

I will tell you that I love my Macbook Pro. As a beginning web designer, I committed fully to Apple, but the choice is a personal one. I would suggest borrowing a friends first to make sure it is for you. (I first started by buying a used Apple laptop and went completely to the dark side once the Intel Core Duo line came out).