While I prefer David Mazzucchelli and Brian Bolland, I voted Jim Aparo. If you grew up in the early 80's, this was your Batman.
QFT! I think it's really interesting how easily identifiable his style is, when it's really a very classic, smooth, "non-styled" sort of style. Sort of like how it's easy to recognize a Ron Frenz Spider-Man. It's obvious, but it's hard to describe why.