Windows 7 better than OS X for Photoshop? Please Help

If you're comparing CS4, yes. And then only if you have the 64 bit version of Windows 7 installed.

The whole advantage was that Microsoft was ahead of Apple getting their OS 64 bit capable. When CS4 came out, Adobe had a 64 bit version of Photoshop ready for it. By the time Apple announced that the then upcoming Snow Leopard was going to have full 64 bit support, Adobe said they were too far into development to have a 64 bit version of PS CS4 ready for OS X.

CS5 is 64 bit in OS X under Snow Leopard. What speed advantage Win 7 had is now gone. I do see that the link you gave does compare CS5 in Win 7 and Snow Leopard, but I've seen other comparisons that show the speed about equal, or OS X with the slight advantage.

But the article says they used CS5.

But the article says they used CS5.

Yes, I noted that where I said:

I do see that the link you gave does compare CS5 in Win 7 and Snow Leopard

There are features in Windows CS5 that won't make it to Mac until CS6. Also, there will likely be updates between now and whenever.

One area where Windows and CUDA play a role with Adobe to off load to GPU and to use Quadro for image rendering - not something your laptop review could test for.
http://kb2.adobe.com/cps/404/kb404898.html

you're using G5, not Mac Pro, may not help.

Good use of more than 4-cores, support for more RAM.
Right now, Double the memory, double the cores, go 32% slower.
Blame it on Apple?
http://macperformanceguide.com/blog/2010/20100905_HallofFameShame--macpro.html

http://macperformanceguide.com/Mac-Upgrade-CaseStudy-MacPro-Memory.html

Why I disable OpenGL in Photoshop CS5
(also, OpenGL 3.x isn't being supported, even as GPUs support 4.0 now)
http://macperformanceguide.com/blog/2010/20100702_PhotoshopOpenGL--photoshop.htm l

About CS5 and 64-bit (and how to optimize)
http://macperformanceguide.com/OptimizingPhotoshopCS5-Intro.html
http://macperformanceguide.com/OptimizingPhotoshop-Intro.html

CS3: G5 Quad vs Mac Pro 2008
http://www.barefeats.com/harper.html

I'd say get a Mac Pro, run both, CS5 for Windows and under OS X, when you purchase your next system. I prefer the Mac Pro's quiet and build, though it does have some limitations, like GPUs that work under OS X.

In real life, there's no practical difference. I run CS5 on both a MacBook Pro and on a Windows 7 machine. I'm also a graphic designer, so I would certainly notice.