The Last Airbender: Legend of Korra has previously been slated for release in Fall 2011, but was later postponed until the middle of 2012, now, however, two separate sources (in a span of a few days) have stated that Korra will be released in 2013. Fans have already begun speculating that it is a rumor or that it is a typo. However, the possibility grows increasingly unlikely as more sources report Legend of Korra is going to be out in 2013, not 2012 as previously reported.
EDIT: Several people have been saying in comments that this is likely due to time constraints, however, this is not the case:
"Except that the addition of the second season did not postpone the air date. I promise. There are other network factors that are playing the role of "delayer." It has nothing to do with the pick-up."
-~Staff member on the air date of LoK
ANOTHER EDIT: Dante Basco has said in his recent interview (which was filmed months ago) that the Legend of Korra finale has been filmed already. That means it has not been delayed to timing.
Please stay civil. You should not harass other users or their views.