This is by no means an exhaustive list. :) It's just a few things I think are particularly nice or underrepresented as outfit choices. I don't have many resources to look at the new things in the game, so there's only one Northrend piece, the Moonshroud Robe.
 Once WoW Model Viewer is updated for Wrath, I might make more of a collage out of these outfits and add a few more. I'll just edit this post for it, but I'll add a temporary "new" post about the change.