Blade Runner's already pretty damn noir, from the colour palette to the pacing. So a trailer pitching the movie as an actual 1940's black and white drama just makes sense, ok?
Creator Chet Desmond says that it's not meant to be an actual re-imagining of the classic flick. "As many have pointed out, Blade Runner is already very 'Noir'", he says. "I just wanted to take those aspects of the film and accentuate them into something hopefully interesting."
Blade Runner Trailer - Classic Noir [YouTube]