I love using Photoshop, and the fact that Photoshop is 64-bit on the Windows side only makes me want Vista 64-bit w/ 16GB of ram. I can get 16GB of DDR2 ram for $330 from Amazon, and around that price on Newegg. Throw in a 4870x2 (2GB GDDR5 memory) video card, a quad core processor, and you have a monster powerhouse of a work station on a budget. $500 for the Video, $330 for the RAM, $190 for the Q6600 CPU (or $320 for the Q9550 CPU). For me, if I am working on something that is hardware intensive, I want powerful hardware to back me up.
For me as a Photoshop user, I much rather have Vista 64-bit on a machine with at least 8GB of ram, quad core, and a decent dedicated graphics card. You can get those specs on a Dell, HP, Gateway for a little over $1K, but if you wanted that in a Mac, you would have to step up to nearly $3000+. Plus, Photoshop CS4 is only 64-bit on the Windows side, so the extra hardware of the Mac Pro would be pointless, as it is a 32-bit app on the Mac side.
For me as a Photoshop user, I much rather have Vista 64-bit on a machine with at least 8GB of ram, quad core, and a decent dedicated graphics card. You can get those specs on a Dell, HP, Gateway for a little over $1K, but if you wanted that in a Mac, you would have to step up to nearly $3000+. Plus, Photoshop CS4 is only 64-bit on the Windows side, so the extra hardware of the Mac Pro would be pointless, as it is a 32-bit app on the Mac side.