I vote Avengers: Earth's Mightiest Heroes. I love this show, and I'd say it's the best superhero team show Marvel has produced so far. It's pretty amazing how much stuff actually happened on the show, and how awesome pretty much every character featured on the show was. Stories inspired from the comics, with plenty of new twists along the way to make things more interesting, and I thought the Secret Invasion story-arc (probably the show's highlight) was amazing. I really enjoyed the characters, the story-arcs and the show as a whole. Even the latter, re-tooled episodes, while not nearly as good as the previous ones, are still pretty enjoyable and much better than anything its replacement show has managed to do so far. It's a shame the show didn't continue, since I'd say there was still a lot of potential for future stories. I think I only watched the first two seasons of Jackie Chan Adventures. I remember liking it, but I just got to vote for Avengers: EMH in this round.