
I am of the opinion that Jeremy Soule could potentially become the next John Williams if he were to move into film (and he's only 35! John Williams didn't start composing his truly iconic themes until he was well into his 40's!), but my favorite soundtrack for a specific game would be Doyle W. Donehoo's score for Warhammer 40,000: Dawn of War II. Just take a listen to this epicness. I was quite shocked to find that he hasn't done anything that notable outside of this game.
Hmm... MechWarrior 2, Dawn of War II... I guess tabletop games have this habit of inspiring great music in video games based off of them.