As this is in conflict with what we've been told so far, my initial thought was it's some sort of misunderstanding or poor use of language. It could be that their word choice is poor. Or perhaps they are unaware of how much smaller The Elder Scrolls III: Morrowind's world (25 square kilometers) actually was in comparison to The Elder Scrolls IV: Oblivion's (41 square kilometers). Maybe they are ignorant to the fact that the world in each game is scaled and are assuming it's smaller because Skyrim itself, according to Elder Scrolls maps and lore, is supposed to be smaller than both Cyrodiil and Morrowind. However, I can't entirely rule out the prospect that they are indeed referring to "the game" in relation to the scaled worlds of previous Elder Scrolls games. And they have actually played the game, so some degree of credence is warranted.
Can someone make me feel better and prove my worrying is ridiculous. If the world in The Elder Scrolls V: Skyrim is indeed smaller than the world in The Elder Scrolls III: Morrowind, then The Elder Scrolls V: Skyrim will have the smallest play space of the series so far.