The Last Airbender is really hard to make a judgement on. At some points the acting is really cringeworthy, followed by scenes with Dev Patel who is really cool. There are sections of dialog that could have been written by a five year old, then visuals that are absolutely fantastic.
I’m sure kids will like it as the problems with the dialog will probably not matter to them, and judging by the popularity of the Harry Potter and Twilight series, acting is not of prime importance either.
I hope they make the next two in the trilogy as I would really like to see what other visuals they come up with.