To Jerf:
I doubt that they will have about 100 of caves, tombs, and dungeons. So I worry about this: travel distances will be too high. First time it is fine - just ride and look around, enjoy the beauty. What about second, third, forth time? I do not want the world of TW3 to have a structure of Arcania world, where you never have a reason to return, and go from area A to area B, to area C, and so on. Also I do not want fast travel to become a necessary boredom-eliminating feature like it was in Skyrim. A huge world makes sense when important and interesting things happen quite often, not when it is just a decoration, and in reality we only utilize a small part of it, skipping the larger part by fast travel. Also I do not want the world to have a structure of Two Worlds 2, where accessible land is not that large, but somehow an ocean is included into the world size as well. This would be real misleading. If the world is 20-30% larger then Skyrim, it should be in terms of accessible landmass.
Anyway, it is just my worry about the world being too big. I hope 100 hours do not include time to get from one location to another. Comparison with Skyrim as the major selling point is another matter. I think TW3 should stand on its own two feet, and be presented and judged by its own merits, and not in comparison with Skyrim, DAO, or other RPGs. I am not a market analyst, though. It seems to me that uniqueness is a key to greatness, and constant stress on Skyrim is a bit immature, or too simple-minded. But who knows what is better for sales these days.