It still looks great, thankfully, but that has more to do with strong art direction and a cool painterly aesthetic than technical prowess.
I revisited Dishonored on both PC and Xbox 360 then compared them to the PS4 and Xbox One versions, and the differences between current gen console and what the PC version was doing three years ago are non-existent. As far as presentation is concerned, Dishonored Definitive Edition certainly does look noticeably better than it did on PS3 and Xbox 360 – higher resolution, better textures, more vibrant colour - but it’s essentially on par with the original PC game running on half-decent gaming hardware. In content terms, this is the same release as the Game of the Year Edition that came out almost two years ago.
Is it a “Definitive Edition”? Not exactly. Dishonored Definitive Edition incorporates the superb original game, the three pieces of subsequent DLC, and some additional in-game bonuses.