Good thread with lots of K-pop
here. I asked a friend who's been living out there for 2 years about other Korean music recently, and he said it was all shit. From what I can gather, there's a minimal Japanese jazz influenced scene and odds and sods of lightweight rock in terms of the modern. I've tried listening to a few traditional compilations, and I can't really hear a great deal of difference between, say, Pipa music and the Korean traditions - though that's likely down to my ears not being attuned to east-Asian subtleties.
If you do find out though, let me know. Also, if you fancy picking up some tapes or CDs while you're out there, I'll happy remunerate you at a convenient point.