Wow, it's been a long time. Just now, I realized that I was thinking something that would make a good blog entry. So:
A long time ago I read someone opining that science fiction was about the time in which it's written. When I read that, I was like, "no, it's about the future, duh". Maybe some things were about their own time, like the hitchhikers Guide series was about the England of the time it was written. Those books are about society, or about some cute jokes; the sci-fi parts are just setting. But then there's SF that's fundamentally about the ideas--taking an idea and working out its implications and seeing how it would affect people. That kind of SF, I thought, bore little relation to the time in which it was written. Just the opposite, actually, with the writer trying to escape from her time and place.
Lately I've been buying lots of e-books from fictionwise.com. One of the great things about ebooks is that the format makes individual pieces of short fiction commercially viable. It's a bit like iTunes in that respect, I guess, so here's the internet punditry ca. 1997 finally coming true, what with the disaggregation and all. Anyway, I've been reading lots of short fiction from the sixties through the present, and it's becoming clearer that sci-fi really is about the time in which it's written. Even in idea-based SF, the ideas being worked out are those of the era. Stuff from the 60s and 70s is all about space travel (Heinlein, Niven, et al), then later (80s-ish) it's about computers and robots (frequently, some combination of computers and robots with space, cf Asimov). In the 90s we have a spate of stuff about genetics (recommended: Nancy Kress, "Beggars In Spain"). Nowadays, we get lots of stuff about the internet, with telepresence, virtual reality, distributed collaboration and computation, and cool shit like that (Cory Doctorow, for example). Of course there are exceptions, but the volume of stories does correspond.
Maybe this is obvious, like of course idea-based sci-fi is going to reflect the zeitgeist, because new scientific or engineering breakthroughs fire everyone's imagination in a similar way at the same time.
Apparently people don't all see the correspondence as going in that direction, though. A few years ago in college I was present for an argument between two people: fuzzy person (FP) and non-fuzzy person (NFP). FP majored in Rhetoric and Political Science, and he thought that fiction drove science and engineering. He thought that a Star Trek-style transporter was not far off. All the engineers he knew were probably Star Trek fans, and it was clear that the imagination side of things had played a role in the career choices a lot of them made. NFP was some kind of engineering major, and he disagreed, saying that science and engineering are really driven by what's possible at a particular point in time. Naturally, I sided with NFP; there's a huge number of scientific discoveries that are purely serendipitous (so much that it's a little depressing), and physics puts a pretty hard limit on what the engineers can do.
All of the sci-fi reading really put this into focus, though. In "2001" Pan Am was making commercial trips to a space station; in 2001 Pan Am was long gone and Mir burned up over the Pacific.
My point is not that SF writers get it wrong sometimes. It's worse than that. With the amount of writing going on, it seems like pure chance would have given us more validated fictional predictions than we've gotten. People like to cite how Arthur C. Clarke predicted/invented the geosynchronous satellite, but interestingly almost no-one actually remembers the story that it appeared in. The story itself was forgettable; the insight was an engineering one, and the story was a bit secondary. The sci-fi stories about space occur almost entirely outside of Earth orbit, but the real effect rocket science had on society has been through ICBMs and satellites. The robot stories focus on humanoid robots, but we don't need 'em. We've got plenty of humanoids sitting around as it is--you can hardly throw a rock without hitting one. The genetic stories are almost all about human germline genetic modifications, but it looks like genetics is going to have a really big impact in diagnosis and drug development, and as a general tool in biological research. Germline mods get done in agriculturally significant organisms (about which very little fiction is written), but it'll be a very long time before parents start putting non-human genes into their kids.
Maybe it's just that the fiction predictions are being made on much larger time scales, and they'll come true eventually even though we haven't seen it yet, but I don't think so. I think the interesting stories are a lot of the time not the ones that are actually feasible or desirable, so the scenarios in them rarely actually occur.