On the up shot, if the map on the cover of Game Informer is anything to go by, you're looking at around 50% of the continent (judging from how big Morrowind is).
While the art direction for Skyrim constantly makes me stop and just... admire shit... (Blackreach was another of those moments, but whenever the weather clears some and you get some awesome vistas it's worth stopping for a moment and looking), I do miss Morrowind and it's bizarre, alien landscape. The marshes, the blight, the canals of Vivec, the crazy-ass mushrooms on the eastern side of the island... it was great stuff. In Skyrim we ride horses and carts between cities. In Morrowind we rode silt striders and blimps and shit. And then there was the solar eclipse...