I am sure there will be camo for all weapons at some point. They may be part of special events, in the dlc, or premium perks that will come in the future. --- Jemas777, Just another guy...by AnyOLName.
the additional weapon and player camos are supposed to be be mid-expansion releases.
so the next DLC expansion is due in September and there is a "Bonus Content" launch in July. then the next DLC expansion after that is Decemeber, so more "bonus content" is scheduled for October and November. this bonus content is titled soldier upgrade and the battlelog says: Unique In-Game Content Soldier Upgrade July, 2012 Get even more unique personalization options with a new batch of weapon camos and soldier camos only for Battlefield 3™ Premium members.