While I am irked about the removal of spells such as waterwalking(that spell made me declare Oblivion GOTY), there is one that almost makes up for it. In Oblivion, I always wanted to play a mage that uses the dark arts and be a necromancer kind of guy. I killed the necromancers for the Mages Guild with a tear in my eye. In Skyrim, Dead Thrall is hands down my favorite spell! You can use that spell infinitely, the bodies don't turn to ash. Nothing beats going about my daily business with General Tullius by my side, and the final kill for the Dark Brotherhood. I am absolutely pleased with this spell and have been dying for it.
PS:How do people know my followers are my thralls, even if the magic appearance fades?