I finally cave in and watched an episode because the show was getting so much praise here. And here's my initial thoughts:

The art style is great, it looks great. The music is amazing and sets the mood really well so I'm a big fan of that.

The writing is average at best, pretty basic for an animated show but good enough to keep me watching. The voice acting is at places horrible but there's a few good actors there that delivered. The comedy relief is sub-par but then again it's aimed at younger people who I think would find it great but for me it did pretty much nothing.

This is the show's biggest problem: Pacing. It was all over the place and I felt like things I wanted to see ended in a flash and moved on to something completely different. I understand that there's time limits for a 20'ish minute show but they really dropped the ball on this one.
It sort of had the feeling of a bad Youtube vlog where the camera cuts after each sentence for no real reason, now of course it wasn't that extreme but it moved way too fast for it's own good. The show would have gained so much if it took some time to address some things a bit longer.
The characters didn't feel fleshed out enough and all of them felt pretty flat as a result, but because the episodes are short I think that requires more episodes than just one.

The action scenes were pretty good, great direction. The bending theme is interesting so it was fun to watch it in action. But sadly when the dialogue is what it is it's hard to care enough when there's fighting going on.

I don't think I'm in a rush to watch more. Maybe if I knew the characters a bit more it would have more of an impact but as it is now I don't have interest in following the series.