As far as I can tell Skyrim's dragons aren't particularly bright either.
More thoughts on the trailer: the character looks kind of barbaric. No shield, mostly dual wielding, animal fur on his shoulders and he's using something resembling a smaller version of the Bastard Sword/Claymore. I wonder what he's turning around for in the forest. He's looking like he's preparing himself for a duel. It's far fetched, but this could mean we get more humanoid enemies to fight like the masked figures, rather than a ton of monsters. Once again, speculation though!
His helmet looks Paladin-ish, with a bit a bit of a Roman touch. If this is a class like the knight resembled a class in Dark Souls, my bets are on a faith warrior. The swords the masked figures are using also seem to be Roman or Greek. We may have a shift from the Medieval vibe here. The quote "forever without light" might be a reference to the Age of Dark, which is bound to come around sooner or later as Dark Souls tells us.
For some reason I also think Bonfires will disappear from the game. It's based on nothing in particular, but if the game takes place in the Age of Dark it makes sense that all bonfires have faded. The torch is on fire though, so out goes the theory.