J.G. Ballard (Score 1)

I nominate JG Ballard, not only for his thoughtful books on how technology changes humanity (Crash, High Rise, and Concrete Island), but because his early short stories are really good science fiction.

Read his short stories such as "The Concentration City" (where humanity has so populated the earth that the only solution is to build onward and upwards), or "The Subliminal Man" (about a society that is so reliant on consumerism it must turn to subliminal advertising to force people to continually buy products) and you can't help but admire his imagination at the implications of technology and society.

Perhaps he isn't flashy space opera, but his ideas are consistently interesting and engaging, and to me, that's a hallmark of a good sci-fi writer.