I'd like to think that the visual/art side is significant in all the games we've helped produce! Check out the one we released right before The Deeps:
http://itunes.apple.com/en/app/killah-killah-whale/id5320424...The thing is so far, none the developers of the 20+ games that we are currently producing knew Objective-C before they started, so the learning side of what we do is important too for many developers.