What is the best laptop for graphic design?

[kb]

I'm after a laptop with certain specs:

1. i dont like heavy bulky laptops, thin & light preferrable
2. i need a laptop that is reliable
3. i will be loading Adobe Creative Suite on to it - so will need something that will perform & be fast while i'm using Adobe CS, example i will have a handful of large sized high res image files open in photoshop
4. i need something that will perform with multiple applications open & running at one time, example music playing, with 5 internet explorer pages open, messenger running, MS word running

I love Sony but one of my "nerd" friends recommended a mac or a dell if i want to spend that sort of money . im not too keen on macs, and i have read online reviews of sony vaio & dell xps laptops but it has just made me even more confused. help!

PS the laptop will be for personal home use plus graphic design work - however graphic design will only be occassional as i do most of it at work.

[emu381]

MacBook Pro