morrowind was smaller than oblivion as well.. but for me it felt 10 times bigger = more content
You mentioned Morrowind, and this isn't against you but a general misunderstanding that many players seem to have (it doesn't help that the title of the game was misleading). We never played the entirety of Morrowind, only Vvardenfell. Vvardenfell only represents about 1/3 of the total area of Morrowind. Minor issue, but this goes for calling Cyrodiil "Oblivion" just because that was the name of the game.
No, there is more content in the same amount of space. How many dungeons and caves can they put in that trek over the mountain?
Exactly. As you can see from the http://www.uesp.net/wiki/File:TamrielMap.jpg, Skyrim is definitely smaller than Cyrodiil. However, they are saying about the same size because - as Mr. Howard very clearly points out in the above linked interview - the mountainous terrain artificially inflates the "feeling" of size, so it will feel about as big because it takes longer to explore area via climbing or winding paths.
Of course, the scale of Vvardenfell, Cyrodiil and now Skyrim are making the world of an awful lot as compared to what we say in Daggerfall. Using the scales they are giving us and the http://www.uesp.net/wiki/File:TamrielMap.jpg, we are only looking at about 250-300 square miles at best. Also, they are saying that both Cyrodiil and Skyrim are/will be about 16 square miles, but they also said that Daggerfall (which just covered the Iliac bay region) was 62 square miles. Yet from the http://www.uesp.net/wiki/File:TamrielMap.jpgyou can easily see that the Daggerfall content is not nearly 4 times larger than Cyrodiil or Skyrim.