hi i need a mac for school and i waited till the end to get the new ipod. i will be using it mostly for school but plan on gaiming on it (a lot actually) so i wanted to know how much of an impact would i have between a mbp 15" i7 with 512mb vram vs mbp17 vs Imac i5 quad core with 1gb vram. i thought that maybe beacuse the stupidly hughr res of the imac (not complaining) frames woulb be about the same. any thoughts? thanks a lot.