Realistically, if you can throw a fireball.. why not be able to blast a foe with fire through your fist?
Since Skyrim will allready require players to equip spells to a specific hand, we can simply add a hand to hand "spell" that enhances your unarmed attacks. This way hand to hand can be enhanced through the magic system, and perhaps we can see some "unarmed focused" mage NPCs (in Oblivion almost no NPCs used unarmed).