i have watched most of the imitation anime on American TV...an i can truthfully say most of it is superficially anime, just the superdeformaty, the still backgrounds, reused cells, and the same antics of American cartoons put in "anime" form. almost none of them really fit in the anime structure of animations.

avatar is a great exception. first of all, if you watch with out the sound, it feels like an anime, the colors aren't overly bright, the movements are real feeling and the action sequences remind me of such great fighting animes like Ranma 1/2 and akura and many other action stories. then you watch with the sound, the characters are young, but not stupid, and unlike most cartoons, the adults are not total retards and the kids to stupid things that kids do, they make mistakes and they depend on each-other and the few adults they do meet in their journey. the chara's evolve though the situations, they have doubt and troubles, they have love they have hate...even aang shows jealousy at one point and does a mean and selfish thing to keep sokka and kitara as his companions.

and that's not even mentioning the plot that keeps me entranced despite having watched and read a ton of stories in the same vein.

i believe that this is a step in the right direction for American animation. i only wish more of the studios would follow in nick's feet and make better animations that attract all ages.