See YALSA's list of exemplary graphic novels here. And since they made finding their top ten a little difficult (what is it with folks this year? Is it suddenly not hip, or is that not hipster [librarians were the original svelte, black-glasses-wearing, know-it-all hotties, afterall], to make top ten lists?), here's a link to it too.
Among the top ten, there's an interesting mix of genres. Even the capes got a nod or two.