I saw the teaser trailer for Dishonored earlier this year and was rather indifferent toward it, but now it has my full attention. If I'm being completely honest, the gameplay does look like it borrows heavily from Bioshock, and there even seem to be some elements inspired by Assassin's Creed. Heck, the semi-cel-shaded graphical style looks almost exactly like that of Bioshock Infinite. But this trailer is so full of atmosphere that I can't help but be excited to find out more between now and the October 9th release date. The fact that Bethesda is tied to the game is a plus.
Also, is it just me, or do those walker things look vaguely similar to the Striders from Half-Life 2?