Sorry if it is already being discussed, but now that we know the DMR AND!! the BR are in Halo 4 I think the loadout system will be like the one in Gears of War.
Maybe something like
choose between DMR / BR / Carbine ??
or AR /SMG / Forerunner?? or Covenant weapon
same with different pistols?
Maybe armor abilities like jetpack are pick ups, I don’t know.
But this loadout system sounds good to me.