Thanks for the overwhelming response. After having time to think through my situation, i'm thinking a $2500 2.8GHz quad core with a ATI HD 5770 would be more suited to my tasks, which i probably should have been more specific about in the first place, while i love gaming and would love to just do that on this beast, most of the time i'm going to be using it for transcending media to play on my HD LCD and for editing HD videos, which I hope will go alot faster on this high-end quad core rig than it does on my 13" MBP. And BTW, the reason i want a MP and not an Imac is bc I'd like to be able to upgrade it and thats not really possible with an Imac w/o voiding the warranty.
But i have to ask, do yall really think that win 7 64bit is the best way to go?
I built my cousin a gaming rig once and bought and installed a 64bit version of Vista. It took 3-4 hours to load, and weighted about 15 GB. He loves to play counter strike, so i loaded steam and DLed CS. I played it for about 2 hours (to test it out

) next day he comes to pick it up, takes it home and the rig was NEVER able to play CS again, in fact he couldn't even get steam to load. He tried to load C&C Generals, could never get it to work. Finally he got fed up with vista 64 and told me to dual boot XP 32 on it, so i did and all the games worked fine on it. Is 7 64bit more backward compatible to 32bit software then Vista bc i don't want to run in to these same problems.
Thanks all
Mat