We know they have skill levels and all that jazz but I don't think anyone's mentioned whether or not they'll have access to the same perks as the player does. In Oblivion for example NPC's got the same perks because they were unlocked by simply having higher skill level (Though this is largely unnoticeable except for melee combat as at high levels you'll start to see NPC's using the disarm attack and even the paralyzing power attack.)
In oblivion those things still occurred rarely enough that they didn't make things too frustrating, but I'm wondering with all the new and powerful effects available via perks whether NPC's will really get access to all the same advantages as the player? (NPC's having 'chance to decapitate' for example could lead to a very frustrating game since there's usually multiple NPC's in a fight...the odds would roll against you pretty quickly and 'cheap' deaths are just infuriating.) But on the other hand them not having any perks at all would lead to my character rapidly overpowering them wouldn't it?