Modern Warfare 2 made it take a lot less time to unlock camos. Gold in MW2 can be done in about a day if you play a bit. Platinum takes more time since you have to get gold for every one in that class. Modern Warfare 2 steps it up for polyatomic, having you get platinum for all 51 currently in the game. Unlocking orion though, it's going to take gamers a long time for that one...