From what I have read of the province of Valenwood, the landscape seems rather comparable to that of the planet the movie 'Avatar' is set on.
Ha! They could base the main quest on that. The khajiit could be invaders trying to burn down the trees and invade and your player has to help the bosmer fight them off. Or I guess... you'd have to join the khajiit and marry some princess. You'd even have cat-people!
I jest.
Though I did vote for Valenwood/Elsweyre. Both provinces sound more interesting to me, especially the conflicts between the two. Not to mention I think dense forest, jungle, tropical coasts, and sand dunes makes for a very cool setting. Of-course there is no guarantee it will be done right. I've never played Morrowind, but I can still feel the disappointed Morrowind fans feel when they play Oblivion. The Cyrodiil written about in past games sounds a lot more interesting than what I played.
None the less, if we get Skyrim I won't be that disappointed. It will still be fun.