There was an unidentified event today in Brazil that unveiled a new Star Wars Rebels poster:
It looks pretty cool. No word on if anything else came of the event in terms of new about the new series coming to Disney XD in 2014.
UPDATE: (from Johnamarie) I thought the poster looked familiar, so I went back to my video footage from New York Comic Con and found that we have seen this poster before. It was red, though. This one is black and obviously in better quality.