I asked yesterday at the Diamond check-in desk as to whether there is any relation of player level to the room key they are issued. The answer is no... The lenticular key and the blue key with the entrance are being used at all desks. Since Caesars became a Harrahs resort, they use player's cards, not room keys as restaurant line passes. The silver and gold keys used to serve this purpose at Caesars but are no longer issued.