Do you need a 256 Meg video card or can you get away with a 128meg. On the new macbooks they come with either on the 15 inch. In general what are you gaining beyond advanced 3D type apps.
Motion, Color and, increasingly, Final Cut Pro all offload processing tasks to the GPU, so the better your video card and the more video RAM you have, the better your performance will be in those applications. I noticed a tremendous improvement in Motion 1.0 when I replaced the 128MB stock video card in my G5 with an x800XT with 256 megs, and I think the difference would be even more marked with the newer versions of the applications.
The name of the game is internal memory...or RAM Bump that baby up and it'll work wonders for your whole workflow... I too recently upgraded to a 4xNVIDIA G-FORCE and up-graded my RAM to 512... and my plug ins are way cleaner and have a smoother look to it... also when applying shadows to my animations it makes it easier to see where i need to give a little more attention to...
This from tech super powers (an apple specialist company in Boston)
"From what I have been hearing the difference in the two models has been negligible for most uses in Final Cut Studio.
The area where the more VRAM starts to make a difference is in high-end 3D work in programs like Motion, and when you are using a large external display."
The macbok pro upgrade in the 15' model is $500 more and really the only advantage is the larger video card. (the increase in cpu speed and 40G extra HD space is negligible IMO)
I won't be using it for animation, but I'm on the fence.