For those avatar fans here a new show is coming up next year. It's called the last airbender: the legend of Korra.
The show will take place 70 years after the end of the original series with a southern water tribe girl named Korra that is the next avatar after Aang. The setting will be republic city where Korra after having mastered water, earth and fire bending will seek the last air bender in order to learn the final element in gher avatar cycle. The air bending master that will teach is called Tenzin and as you might guess he is Aang and katara's son.