Hi, I'm about to buy a new iMac and I'm trying to decide between getting 1 GB VRAM in the video card or 2 GB. Isn't Lion supposed to farm out more processing to the GPU than prior versions of OS X? I thought I read something about Grand Central Dispatch using OpenCL automatically. If that's the case then I wonder how much video memory it would want to use. Can anyone comment on this? Is it likely that down the road having the extra VRAM could lengthen the iMac's useable lifespan, since future OSes and anything using GCD will gain some kind of miraculous performance gain from OpenCL? Thanks!