That's an interesting observation, and one I hadn't noticed, until it was pointed out, and, well, I don't know what to make of it, it definitely looks like a quiver there and the other thing could be a bow, but I don't want to assume too much from just that, as based on what we've heard, it sounds to me like we'll only be able to equip more than one weapon at one time for dual wielding, and I certainly doubt we can dual wield bows. So unless the game has some way to display more weapons on your character model than just the one you're currently using, I doubt we'd be able to have a bow on your back and other weapons in your hand.
You see, that's what I'm actually thinking. But I see no compelling evidence that the Draugr are not fundamentally unplayble NPC's. Different Animations (Especially given the engine changes) and clothing, which could be compared to the unmodifiable underwear of normal races, are not compelling counterpoints.
I'd imagine that the draugr are indeed some form of creature with their own unique models at all, and not a race that functions like the default playable ones, but is not playable, and their clothing is likely actually part of their body model. Even so, they're weapons are likely actual weapons you can loot, much like say, goblins in past games, so if you see a bow on one, it seems likely that it's actually a bow, and not just part of their model.
Though mostly, I just think that's the case because in past games, something like the draugr would usually be handled like that, but maybe things are different in Skyrim, we'll see, certainly, if it's true, than it would seem like there is more than one model for draugr, as the different individual draugr seem to have some cosmetic differences, both in clothing and other areas, which is really the only reason I'd even consider the possibility of them being an unplayable race, but it could also be that Bethesda has decided to implement some variety in creature models, which would be a welcome change from having every creature of the same type apparently be a clone.