Worlds and Monsters really had me excited for where 4e art looked like it was going...evocative, jump-right-in landscapes and scenes...but for some reason it never went there. Adventure modules in particular should each have a full-colour piece of art that shows the module's setting - the castle, the lake, the hills where the caves are, whatever - so the DM can hold it up and say "You are here".
Whoever it is who insists on always depicting adventurers with enormous weapons (insert double entendre here) has to go.
Lan-"art and death are both in the eye of the beholder"-efan