It appears that Amazon has posted box art for Season 3 of The Clone Wars. This art currently only appears on Amazon UK's listings for the DVD and Blu-ray sets. So far, Amazon US does not have art on its DVD and Blu-Ray listings.
While no announcement has been made regarding these sets, Lucasfilm's Chris Argyropoulos confirmed to TFN that this will be the real box art.
Special thanks to fan of TheForce.Net "Chewgumma" who wrote in to give us the heads up!