I've always loved the Elder Scroll's theme song, ever since the "wandering" theme in Morrowind. The Nordic Choir singing along to the theme for Skyrim however, made my metaphorical jaw drop.
Also if you haven't noticed, the "wandering" theme from Morrowind (a variation of the TES theme) is almost exactly the same as the one you can sometimes hear in Skyrim. The only place I can solidly say I heard it being played was in Whiterun.
However, given the fact that it's the Elder Scrolls theme, I can't say I'm surprised it returned, and I'm likely mistaken that it's exactly the same as the Morrowind one.