To keep branding consistent, Sony updated the design of their PlayStation 3 boxes to match the slim PlayStation 3.
Gundam Senki uses the new design which drops the Spider-Man font and sidebar. Revised boxes have a horizontal header with the slim PS3 font and a PlayStation Network logo if the game has online play. Doesn’t seem like there’s much room for an “only on PlayStation” stamp, though. Japanese PlayStation 3 games don’t get that label so Sony may alter the design one more time.