For those who have the NickToons (NToons) cable channel, the final arc of "Avatar: The Last Airbender" is currently being aired. This goes up to the series finale, with Ang having to face the Firelord and end the threat of the Fire Nation. After that is the premiere of the new series "Wolverine and the X-Men" at 8 pm EST. Not sure why Nickelodeon chose to put the new X-Men series on NToons instead of Nick itself. Even in these modern times, not everyone has all the higher cable channels.
http://nicktoonsnetwork.nick.com/shows/wolverine-and-the-x-men/commonRoom/index.jhtml