Arkham City is amazing all around. I won't spoil it if ya don't know, but there is a clue that the next game could be Batman Beyond. I'm not talking about the DLC costume either.
Anyway, I really dig the song! Composition is great. My only issue is with the piano around 2:05. I can't quite figure out why, but I just feel like there was some better instrument choice for that part.
I think this would be absolutely phenomenal if you could get a real orchestra to play it. I don't know if that's even feasible or not, but if you could get at least some of the instruments like the strings done by an actual string ensemble it would be that much more awesome.
BAMF work regardless, sir.