In the most recent issue of Game Informer, The Legend of Zelda producer Eiji Anouma comments on the future of Skyward Sword's art style and its fate in the Zelda universe:
With Wind Waker, the graphics were suited to handheld gaming. Also the game ended with Link embarking on a journey, so it left open the possibility of what comes after the game. With Skyward Sword, positioning it as the first Zelda game means everything else connects to it and comes after it. It becomes a little bit difficult to do something else within that world and certainly much more difficult to do something that comes before it.
This isn't a direct statement, but it essentially means that the possibility of Skyward Sword's acclaimed graphics will be discontinued, which will be a shame given its potential. But I'm sure whatever Zelda looks like on the Wii U will be stunning, nonetheless.