Very impressive. I think it's interesting that this show will be going up against Young Justice. First time I can remember Marvel and DC having cartoons airing at the same time in years.
What interests me most about this cartoon is the sheer volume of stuff going on. You have the Avenger's individual character arcs, the supervillain prisons, Loki's machinations, Hydra's machinations, SHIELD's machinations, whatever the hell Kang is up to, and of course the actual Avengers forming. So much is going on.
Also, Wasp seems to be the kid-appeal character for this series. That's amazingly appropriate.