Art that impresses me usually ticks off the items on this list:

-It has a conscientious composition that leads the eye
-It is stylized but technically skillful in a traditional sense
-It is full of small, loving details
-It tells an interesting story
-Its individual components combine to create a strong atmosphere
-It exaggerates proportion and perspective to create a dynamic image
-It does something to engage the viewer, breaking the fourth wall or the picture plane

Neal Adams' comic pages for Batman (inked by Scott Williams) meet all these criteria. My favorite part of these images is how they break out of the panels sometimes, but the dramatic lighting and perspective, technical details, and clear narrative flow all make these pages really exciting for me. Another great thing about comics in general is that the viewer sets their own reading pace, so it's a medium I really enjoy for that layer of interactivity.
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