I tried to think about the classics like Koshiro, Uematsu, Kondo, etc.
I have heard their music so much that it no longer really moves me. I still enjoy it and it's still all very good, but familiarity has bred a bit of contempt in me for that stuff. Whenever I'm taken with listening to a game soundtrack, I tend not to pick anything by them because I've heard it a million times now,.
My current faves would have to be:
Hitoshi Sakimoto
Keiichi Okabe-Nier and Drakengard 3 both have amazing soundtracks.
Hedeyuki Fukasawa-Street Fighter IV series, Marvel vs. Capcom 3 series, and especially fucking Chaos Legion and Shin Onimusha, which are two of the greatest soundtracks of all time.