55 deviants said The storyline; I don't care if the art isn't quite up to par (or downright sucks), as long the story is interesting, creative, flows nicely, and uses correct grammer. The story is what usaully makes it or breaks it for me.
31 deviants said The artwork; if the art's absolutely amazing, the storyline doesn't have to be outstanding. It's gotta have good layout, anatomy, style, and easy to visually follow. If the thumbnail doesn't catch my attention, I'll probably not give it a second thought.