Ugh.. I'd like to avoid BB, the G74 being sold there have the lesser version of the GTX 560m. You see, the Best Buy model (2GB vram) has a 128 bit memory bandwith , and the best 560m version (1.5 and 3GB vram) has a 192 bit memory bandwidth... Besides, there is no way in hell these cards have enough power to actually use that many vram, so I guess the only important factor here would be the memory bandwidth.
I've found around the web that there are new asus and toshiba models coming out, the Asus G55/G75 and the Toshiba Qosmio X870 with better specs than current models.. I guess I'll just have to wait and see for prices and retail avaliability