The biggest growth in science fiction publishing these days, hands down, is happening in the young adult market, and that's great news. While the "real" science fiction publishers are chasing a shrinking - and graying - readership, tweens and teens are discovering SF for themselves, thanks to books from a diverse range of writers. Best of all, YA science fiction isn't aimed at a subculture, but at everybody of a particular age.
It's been 20 years since Bruce Sterling compared the "mainstream" of science fiction to a fossilizing Politburo. Since that time, the situation has only gotten more dire. People are constantly remarking on the graying of science fiction readership, but statistics seem to be hard to come by. Here's Tor's Patrick Nielsen Hayden talking about the fact that almost no people born in the 1970s or later have won Hugos or Nebulas. (And in the comments on that post, there's lots of assertion that WorldCon's attendees were skewed towards an older demographic, but no hard numbers that I can see.) Here's an amusing essay from the New York Review of Science Fiction analyzing an issue of Asimov's where every single story is by an older writer and is about getting old.
Meanwhile, young-adult science fiction is exploding. According to John Scalzi, the top 50 young adult science fiction/fantasy bestsellers sold twice as many books as the top 100 adult science fiction/fantasy bestsellers. As we mentioned before, there have been hardcore post-apocalyptic novels for kids and young adults for decades. With more on the way. And with City Of Ember finally being adapted to a (hopefully) major movie, more YA readers than ever will be looking for similar stories.
It's great news that young people are getting exposed to SF at an impressionable age, without apparently feeling any particular stigma about it. And yes, a lot of those people will eventually come to view SF as "kid stuff" and stop reading when they reach adulthood. But if even 20 percent of those readers keep reading SF after they turn 18, that guarantees a sizeable readership for SF in decades to come.
The other great thing about YA science fiction is that people come to writing it from all sorts of angles. Some YA authors write non-speculative YA books and then drift into writing books with science-fictional plots. Some "real" SF writers, like Cory Doctorow (and Scalzi, whose new book Zoe's Tale is being marketed to both adults and teens), try their hands at YA fiction. And then there are "literary" writers, who would never dream of trying to write a grown-up SF book, who find themselves writing for the YA market. I was having lunch with a literary author, an MFA who teaches creative writing and writes for journals like Ploughshares, and she was telling me her agent had told her the big New York publishers were looking for YA books with scifi or fantasy elements, and she was trying her hand at one. Dale Peck, who's now co-writing a science fiction novel with Heroes creator Tim Kring, started in speculative fiction by writing the scifi/fantasy blend Drift House series, about time-travel and a tapestry that shows the future.
Meanwhile, "science fiction" as a publishing niche refers to a segment of books that appeal to a particular segment of people. Call it "nerd lit." You don't have to be a geek to read science fiction - just like you can dress in Banana Republic and listen to Death Metal or Goth/Industrial music. It just helps. You're more likely to find your fellow Vernor Vinge enthusiasts at a gathering of sysadmins than at a dressage meet, or a stockbrokers' convention. Science fiction is stories written by geeks for geeks. (I'm a nerd myself, so I'm not being obnoxious here.) Your average SF novel nowadays assumes you belong to that culture from the outset, and you're used to a whole range of concepts and stylistic tics that might put off other readers.
Luckily, we can have both grown-up science fiction and the YA version. But to the extent that one is shrinking and the other one is growing, that may not be entirely a bad thing. Look at it this way: is it better to have SF written for a subculture, or anybody of a certain age?
The readership of "regular" science fiction books is a defined group of people with a shared set of interests, who dress a particular way and talk in a "nerd accent." The readership of YA books is anyone of a particular age. So, in a sense, YA books have a more diverse readership and are more welcoming to outsiders. Grown-ups might feel silly reading a Scott Westerfeld book on the subway, but there's really nothing to stop you doing it anyway.
Bottom line: We're lucky to have both YA literature with science-fictional themes and "regular" science fiction. There's no reason we can't have both, and appreciate both for what they are, including the innovation and breadth of concepts that mature science fiction can explore. But we should especially celebrate the awesome potential of YA SF to revitalize the field, and bring new readers to SF concepts.