I think the iMac i7 27.5" is fantastic except for the GPU. Why would have Apple used 4850, I've read it's possible it's the mobile version that offers even less performance than the desktop version, and on top of that it's possible that Apple underclocked it to reduce TDP (What does TDP stand for, thermal something?). Is it because there's not enough room, or a better GPU generates too much heat or simply that there was just nothing else better to use? I think the iMac needed the GTX 285 1GB and the Mac Pro needs a new consumer card with 2GB memory. I'd be interested to here what people think.