I think the main quest isn't mentioned much or looked forward to because frankley, it's just not that interesting We have to kill Dragons and do a bunch of other crap so we'll be strong enough to fight the even bigger Dragon who wants to Eat The World?!
that and there's just too much other game to explore. I'ld be more excited for the story if half of it wasn't ruined via previews and it was well written.
I'm not that into dragons at all, and had a really weird mixed reaction when I saw the first trailer. I both realized they were actually making another elder scrolls which is crazy awesome and realized it wasn't going to fit my style at the same time. When I first heard "Dragon Born!!!" I wanted to cry. Maybe I did cry a little. That being said, I think the concept has potential and even though it's not my thing, I don't think the lack of spoilers in advertising is a reason to get all pessimistic about the writing, TES has some great writers and puts out way too much impressive work for me to understand the pessimism.