Really what I want most is Dark Brotherhood and Thieves' Guild quest lines and skill trees. But both kind of rely on the existence of some kind of crime system to work (especially the Thieves' Guild). Plus, a crime system is such a central part of the Elder Scrolls experience to me. But I suppose it's not an easy thing to integrate into an MMO, so my hopes are not high for that.
I have faith that they will be able to add the TG and DB in a way that both fits with the existing lore, and is MMO friendly. I wonder what will come after those two though. I'm sure they have ideas for future skill lines and guilds, curious as to what they will be. On that note actually, I'm curious where this game will be in a year in terms of how much it will change if they release new content as much as they say. We'll see I suppose.
We're getting so close to release, my scales are quivering.