Mac's are very nice machines but my friend that I was talking about early looked into Mac first but the price was to high, with the setup he got he was able to get 12 gig of RAM and Mac didn't offer that , over two gig was extra and drove the price up even higher. But , Mac's are nice machines, I just wish the price would come down. I have been working on win 7 off and on for about a year and I finally bought a copy for my AMD setup.
It kicks butt on XP. I haven't seen any difference in performance between the mac's I have worked on and my friends core i7 PC , I work on his machine a couple of times a week. I do music , Video editing and Graphic software such as Adobe suite, no problems with win 7.
I think win 7 and Intel core i7 have pretty much evened out the playing field if you are running 64 bit win 7. I wouldn't say that if I was talking about XP verses mac though, LOL.