I have a 15" macbook pro and I love it. Depending on what sort of work you're doing though will determine whether or not one would truly be beneficial to you. Programs like Parallels and Fusion allow you to run Windows 7, XP, 2000 or Vista. I run 7 on mine and I haven't had any compatibility issues with the PC programs that I have to use. Whether or not that holds true for all programs I couldn't tell you.

My mac does everything I need to plus some. I have been using them since 94 and haven't looked back since. Yes they are more expensive out of the box, but I feel it's more than worth it in form, function, power and beauty. My brother is an engineer for IBM and gets a crazy discount on their products. I am so pleased with macs that i still chose paying the full price for my macbook pro than getting a IBM for almost half off.