James Marsters On Why A Sequel Would Suck.

Yes and no. Sokka and Katara appear quite dark whilst wearing a light blue, but against other colors, they're not as dark. Plus as the series continued, their skin lightened slightly from not being in the arctic sunlight. Not much, but a little. But also worth noting: can we really say they're actually Inuit per se, as most do not have Blue eyes and all the Water Tribe does? Standards work both ways: all it really is is a fictional tribe which was influenced culturally by the Inuit people.

People are frankly making it a bigger issue than it needs to be. I'd be more concerned about the rest, which is still looking pretty good from what I can see.

EDIT:
Okay, in all fairness, I just found this, so don't kill me for not adding an edit, but:

http://lastairbenderfilm.com/category/interview/

Those are some little tidbits about the film. Including proof that the Asians are to be represented by the Earth Kingdom and Toph herself is inteded and always was inteded to be Asian.