My girlfriend has one of these Mac Book Pro things, I gave it a go the other day.
Everyone goes on about how quick they are and how smooth, well trying to flick through thousands of pictures took a while as it took so long to load, opening applications and although when it finally did it, the apps loaded quickly, it seemed to take a while before trying to open it.
My 4 year old HP Pavilon with 4GB RAM and Windows 7 opens things instantly and can scroll through pictures at ease!
Personally, I don't get the Mac hype.