From the Nickelodeon Executive Q&A on Reddit:

Can be found here!

Q: Has Nick ever considered using viral marketing techniques? I’m asking because many people now suspect that Nickelodeon, or an employee thereof, is responsible for the recent flood of Korra-related leaked clips and screenshots. If not, how do you usually handle leakers?
A: I don’t know if the company has any plans in place or in the future but I do know that we are involved in social media and are always going to have to adjust to how people hear about or receive our stuff.

With that said, no the leaks were not intended. People who steal stuff and go against the wishes of the creators by posting stuff are scum. The world does not belong to you (one) just because you think it does and it hurts people even if you don’t think it does. How we track people and deal with them I probably shouldn’t say…other than “hopefully harshly”. 

Q: How do you guys feel about the Legend of Korra leaks around those parts?
A: I answered this elsewhere. I’m not a fan. I mean I know it has been forever since the last series and people are excited but it is still wrong. It screws a lot of people out of their hard work and is damaging in many ways.

I was very happy with all of the positive feedback it got, if anything good came out of it. There was very little negative feedback which is good…but I didn’t expect there would be as it is awesome.