I saw the trailer, too. I was getting my son some applesauce when I looked up and saw it playing. I was so suprised that I almost spilled the applesauce on his head, LOL.
It looked like it was the same footage as the trailer released in Brazil, and said something like "New episode coming in July." They're showing MightyB! again at 6, so they might show the commercial again. MightyB was kind of annoying, but if you get to see the Avatar commercial, it might be worth it. I'd record it, but the computer with the DVR that's hooked up to the tv isn't working.