An old article written by Paul M. Sammon about a visit to the Blade Runner set during filming. Paul M. Sammon would later go on to write the definitive book about the making of Blade Runner, Future Noir.
In this article he mistakenly writes that it takes place in "New York in 2020". While Blade Runner was at one point intended to take place in New York, I'm pretty sure that by the time they started filming it was already changed to Los Angeles. The year 2020 was also dropped and changed to 2019 because of it's association with perfect vision.
Sammon also mentions "Spinner chase sequences" and "black hole guns". Of course there is no Spinner chases in the final film and the black hole gun was dropped although a remnant of a visual effect still remains in the film and can be seen when Leon gives Holden the good news.
Note also Ridley's aversion to the term "android", a taboo word on the Blade Runner set.
