A local writer, Eric Scoles, has made me aware of an interesting controversy on the Internet (I'm never aware of anything on the Internet without outside assistance). Fueled in part by a GOH speech by Geoff Ryman, a group of writers and readers are advocates for "mundane SF." This is Sf that avoids many of our field's tropes, such as FTL and time travel and immortality, in favor of fiction that grapples with the reality that humanity's future most likely lies on Earth, amid the actual messes we make for ourselves here. Mainstream commercial SF, this argument goes, is mostly about an imagined past of derring-do and adventures transported to an unrealistic future with great tech.
What do I think about this? I think Geoff Ryman has a point, but I also think that it needs looking at more closely. A book like, to take one example, Ursula LeGuin's masterpiece THE LEFT HAND OF DARKNESS uses many of those "tired SF tropes:" FTL, aliens, a galactic federation. But they are not what the story is about. What it is about is the difficulty of seeing past our differences to connect with each other, and the costs that such connection exacts. It seems to me that "realistic" SF depends less on accurate depiction of the future than on accurate depction of human beings.
On the other hand, I like and have written near-future, Earth-based, alien-less stories, quite a lot of them. The category seems less important to me than the specific story.