I wasn't expecting too, but I actually like it a lot. Some people complain about the art style, that it tries too hard to be anime and just comes off awkward (a-la teen titans), but I found it a successful fusion (re-convergence!) of japanese and american animation/art styles. I am continually impressed by the quality of motion animation (especially the battle sequences) and detailed environments. The characters are all pretty cool too, my favorites being Sokka, Zuko, and Iroh.

Anyway, I'm about halfway throught he 2nd season, and I'm already sad I'll have to wait a while to get some more ^_^;