The Legend of Korra, the new incarnation of the Avatar: The Last Airbender series.
If you can get over the fact that it's a kids' show, it's one of the best-crafted series out there. I used to say it was the best animated series I'd ever seen, but now I'd go further and say it was the best show I've ever seen in any genre aimed at any age group. To properly catalog its qualities would take a fairly substantial effort on my part and produce a fairly lengthy piece of writing, so I'll just say this: it's a series that's obviously produced by extremely talented people who deeply care about what they're making, and the more you watch the show the more evident that becomes in a ceaselessly pleasing array of ways. I literally can't endorse it enough.