Science-fiction tends to be speculative, and that's a good thing. It doesn't really try to "predict" the future, per se--just use the genre to tell a story that may or may not seem feasible in the real world. The "fiction" part of science-fiction allows for most any setting and plot lines the author/film-makers can imagine. The time frame can be any period in the past, present or future. The "science" aspect of science fiction frequently (but not always) tends to cause the setting to be in the future. Time travel stories/movies are a notable example. Usually the time machine apparatus is invented in the future ("The Terminator" (1984)), or the present ("Back to the Future" (1985)), and the protagonists of the story can then travel to any point in the past or future ("Bill and Ted's Excellent Adventure" (1989)...).
Now, when a science-fiction story is set in the future, the author/film-makers can choose between a couple of different ways to express when the action is taking place. The first method is to simply describe it as "the future", "the near future", or the futuristic setting can simply be implied by the story itself without needing to state it outright. What makes this method effective is that no matter when the story is read (or the movie watched), it will always be taking place in "the future". The other method is to explicitly state the time that the story is taking place in. This gives a sense of just how far into the future the story is unfolding and gives a sense of relativity to the reader's/viewer's own refernce point in time. This is perfectly fine with a newly published book or a recently released movie, but poses a problem when reading older books or watching older movies. What was "the future" in the story might actually be "the past" by the time someone reads/watches it. With the possible exception of Nostradamus and other future predictors, no one really knows what the future is going to bring. This is what makes science-fiction such an interesting and wide-open genre. One can speculate any kind of future that one can imagine and make an interesting story out of it. Of course, when the time of that story actually comes to pass, the "predictions" made in a future-based story will almost always not reflect the present world's reality.
There are many examples of this paradox, and more are happening all the time. I haven't done any exhaustive research on this topic, but here are a few examples that come to mind from my own movie-watching experience. "2010: The Year We Make Contact" is a very topical example, because 2010 is about to expire with no contact (that I'm aware of) with a higher intelligence from "out there". Jupiter has not collapsed in on itself, and it's going to have to do it pretty quickly if it wants to beat Dick Clark ringing in 2011. Of course "2010" was the sequel to the better known "2001: A Space Odyssey" (1968). Both of these movies were based on Arthur C. Clarke books. As of tomorrow, the dates of both movies will be in the past. Clarke DID write two more books in his series, "2061: Odyssey Three" and "3001: The Final Odyssey". There's still quite a while before the book set in 2061 becomes dated, and 3001 is definitely going to be safe for some time.
Big Brother was watching us in the George Orwell novel "Nineteen Eighty-Four" and a couple movies based on that novel. 1984 probably seemed pretty far in the future when Orwell wrote the book in 1949, but obviously it is now pretty far in the past. My interest in science-fiction really solidified in the early 1980s so I remember hearing about the movie version that was released in 1984. I have never read the book or seen the movies (though I probably should), but am somewhat familiar with the whole "Big Brother is watching" theme. While 1984 came and went without Orwell's dystopian predictions coming true, the idea of "Big Brother" really has become part of our collective conscience. Whenever there's fear of loss of personal freedom or privacy because of corrupt government, identity theft, internet security issues, and the like we tend to hear something about "Big Brother".
The "Terminator" franchise is based on time travel, so some of its problems with time catching up with it can be explained away, but when you get right down to it, Skynet was supposed to become self-aware in August of 1997. It wasn't long after this date that the computers declare war on humanity. This date can be adjusted as the series continues by saying that the heroics of the good guys in the movies (TV show, comics...) caused a delay in when Skynet finally went online. Now that's science-fiction at work! The original time traveling in "The Terminator" occurred when characters were sent back to 1984 from the year 2029, so there's still a little while before that becomes dated.
Another 1980s-based time travel series of movies is coming close to a time of reckoning itself. "Back to the Future" (1985) is pretty safe. In that movie, Doc Brown invents a time machine in the present (1985) and Marty McFly travels 30 years in the past to 1955. No problems there. But in the first sequel to the movie, "Back to the Future Part II" (1989), Marty and Doc Brown travel into the future. How far in the future? All the way to the year 2015. As of tomorrow, 2015 will only be four years off.
TV shows aren't exempt from these time problems either. I first started watching the original "Twilight Zone" (1959-64) back in the early 1980s, when the show was already 20 to 25 years old. I remember at least a couple episodes that took place in the 1980s. It was interesting to hear that (seeing as how I was actually living in the 1980s), but it obviously broke the mood of a story that was supposed to be taking place in the not-too-distant future instead of the present.
"Space: 1999" came out in the mid-1970s, so the year 1999 was pretty far away at the time. Of course, the show (as well as Prince's song "1999") is now more than a decade out of date. It is now almost twelve years after the show was set, and (last I knew) the Moon is still very much in orbit around the Earth. The whole millennium era (1999, 2000, 2001) has always been a tantalizing setting for science-fiction stories. The simple change of century and the simple amazing-ness of imagining a year called "Two Thousand" instead of "Nineteen-Whatever" just seem made for sci-fi. Well, at least it SEEMED like an appropriate setting for stories filmed or written many years before the actual year 2000. Strangely enough, the real world had a very sci-fi-esque potential problem as we actually approached the millennium--the Y2K Bug. That turned out to be nothing much, but had the potential of being a very effective science-fiction story come to life. A world that had allowed itself to become so dependent on computers and technology (cell phones, satellites, the internet...) suddenly finds itself plunged into a new Dark Age when all that technology suddenly and completely stops working.
The TV show "Lost in Space" premiered in 1965. The story was set in the year 1997. I'm sure 1997 seemed quite distant in 1965, but of course now it's even more dated than "Space: 1999". When they made a movie out of the show in 1998, they adjusted the setting to 2058. That ought to keep reality from catching up to the movie...for a while at least.
I suppose the next date to be concerned with is 2012. Not only does the ancient Mayan calendar predict that the world will end in 2012, Hollywood recently gave us a movie about the world ending in that year called..."2012" (2009). I haven't watched that Ronald Emmerich-directed, John Cusack-starring special effects bonanza, but probably should before 2012--just in case the world ends and I don't get a chance to watch it later. While I understand why the film-makers chose to name this movie after the year 2012, they could have easily avoided the problem of having an outdated premise in a couple years by using a title more like 2004's "The Day After Tomorrow". While I didn't find that one to be a very good movie, it does have an almost perfect, foolproof science-fiction name. The day after tomorrow indicates something in the VERY near future, yet it's a date which will never actually arrive in reality. The day after tomorrow will ALWAYS be in the future!
HAPPY NEW YEAR!