Anyone notice Jorge mentioned Pegasi, if he talking about Pegasi delta than it sounds like the new guy maybe a spartan 3.
If thats the case it could well be more of them are also spartan 3's which would explain the skull paint on the big guy as well as the rest having their helmets off.
Spartan 2's were rarely ever shown to have their helmets removed in books or in the game with the cheif, how ever the spartan 3's were not trained from a young age they were recruited which would explain the loose military attitude and removal of PPE[Personal protection equipment] in a combat zone.
E: gah lag beat me to it.