I don't understand; someone said gaming performance does not equate aperture performance. I am not at all interested in games; I just need aperture to function as well as possible short of a mac pro.
I'm not really that knowledgable on what programs use what hardware, but I don't see how Aperture, or Photoshop, or iMovie, etc. would be that demanding on the graphics card. I would have thought that it would be mostly based on CPU tasks. Therefore, there would not be that much difference between the iMac and the MBP, and the bigger screen on the iMac would be the biggest selling point.
Of course, I could be wrong, in which case the 7600 is like 50% faster than the 7300.
Oh, and in terms of your comment about the 256MB GPUs, you could treat a graphics card like a mini-computer. If you want to tell by looking at specs of two computers which is faster, what do you look for? RAM, or CPU? If you double the RAM in a computer, how much of a performance gain do you see? Not much. What happens if you either double the number of cores, or double the frequency of the CPU? You get a huge increase in speed. It's the same with GPUs. A 2GB X1600 would be completely pointless, and a 128MB X2900XTX would probably flog the pants off it. Assuming either of these GPUs exist, which of course they don't.
Basically, just get the 24" iMac with the 2.33GHz, 2GB RAM and the 7600 just to be safe. I don't know how much the GPU upgrade will benefit you, but it will to some extent, whether huge or tiny. It can't make the computer slower, after all.
