...thank gawd korra is a older teen cuz 12yr old Aang was just too kiddie 
Actually he's confirmed still alive by the creators (he's in his late 80s during LoK). He's retired and his daughter is the current Firelord.
http://avatar.wikia.com/wiki/Zuko
It's unknown whether he'll appear in Season 2.
The only people confirmed dead are Aang (obviously) and Sokka (mentioned in the 1st episode). And obviously Katara is still alive. Besides them, everybody else is unknown.
7pm ESTWhat time this come on?![]()
Korra's uncle is sounding sneakily evil so far