Winterhold is also where the Mage faction is, which is weird because Winterhold isn't a major city is it?The five major cities are Windhelm, Whiterun, Markarth, Riften, and Solitude, are they not?Did they add Winterhold as a major city or are they just trying to pack too much into a minor town?
It will probably be something of a hybrid. A MAJOR village/fort or a minor city. Something perhaps like The Arcane University, but entirely isolated rather than connected by a bridge to a major city. Or, if it is open, it could be like a couple of the larger villages of Oblivion put together and centered around a tower.