you can have flamethrower hands thanks to an altered magic system. need I say more?
ok, maybe I do
you basicaly have continuous, weaker spells or spells that fire a ball of lightning or something like that that causes a lot of damage and has a fairly large explosion.
also, the bandits and wildlife are much more threatening in this than in oblivion and actually look like they would IRL (e.g. no more wolves that look like dogs, they look like great big bastards)
also, you have creatures like draugr which pose a very minor problem, until you start to come across the restless and Wights, they can really become a problem.
skeletons, however, are weak as hell. one shot from a longbow with an iron arrow = them dead.