I love Macs alway have and always will I use my mac book pro all the time.... yet for running Photoshop CS4 and Light room, I love my home made Vista64 box with a nice Intel Quad Core Processor, 8 Gig's of Ram and 3 10K RPM Sata HD's 1st HD for OS, 2nd for OS scratch and 3rd for PS scratch. My system flies and for a quarter of the price of a Mac Pro, which I think is an amazing machine, and would love to have one, but I am waiting for true 64 bit PS and sounds like this may not happen for quite some time.
I know everyone will laugh at me but aI am very excited about Windows 7 64bit which I have been running RC1 on another 10k RPM drive i have installed and it really runs very nicely.
Apple hardware/OSX is great don't get me wrong, yet for me I would rather save the money on my computer purchae and buy more lenses or save up to go to exotic places and take more photo's
Just my 2 cents
Steven