The main thing that makes Skyrim such an exciting prospect to play in contrast to Oblivion is that not only do we have the dragons return to contend with (and sort out) but as a player, we also arrive at the time of the conflict between the Imperials and the Stormcloaks. We are made aware of this right from the beginning and I for one can't wait to see how it all pans out, it makes for some really involved game playing and some interesting story lines. Will I as a player take sides? Or simply stay out of it? What will you do?

The thing that makes Skyrim so exciting is the do-whatever-you-want design of the game. That...and the large amount of phat l00tz.

Being able to do 'what ever you want' in Skyrim is what gets me excited. And having Dragons just makes it super attractive.
I have never been this excited for a game. Actually I have never been this excited for anything!