For those who care, there were hidden decals released with the last patch. You can view them by going to your player profile -> achievements tab -> special. There's achievements for killing 40 planes in any plane (or 20 in Dora's) and 30 planes in bombers and one for 20 kills in sherman tonks or 40 total kills in any tank. Once you've earned them it's under specials. Also, the decals are only available from now till April 3rd.