5. Near-future science fiction
8. Military science fiction
Near-future SF tends to be centered around the technological advances that are just around the corner from us, and sometimes they involve socio-political changes, but that is not always the case. Precisely because of the near-future time setting, the society in which the story takes place has not really changed that much, and if it has then it's not near future SF but another of the sub-genres.
Cyberpunk deals primarily with the effects of merging technology with humans (cyborgs, direct neural inputs, immersible computer networks), and the results are more often than not bleak and despairing. This leads mainly to two kinds of stories, adventure and thriller, but unsurprisingly the existence of such a close relationship between man and machines, has a profound impact on the socio-political background of the story, and in some this can be seen more clearly than in others, being the best example William Gibson's Neuromancer.
The Cross-genre sub-genre, being on the meeting point between SF and other genres, has the potential to touch upon any number of subjects, and occasionally these subjects have a high degree of socio-political influence, as in the case of Marion Zimmer Bradley's Darkover series, where in some stories you can clearly see the Science Fiction underpinning the story, like The Saga of the Renunciates trilogy, while others are definitely more of a fantasy setting, like stormqueen.
And last, but not least, is Military Science Fiction. This sub-genre might the one most used, and abused, by the motion film industry; think of the hundreds of movies involving futuristic wars, with an international/interplanetary/intergalactic army at the center of the story, trying to blast the enemy into as many pieces as possible, and no story beyond that. But in books this is not so; take for example Starship Troopers (the book by Robert A. Heinlein, not the movie directed by Paul Verhoeven) an look at the amount of time dedicated to the socio-political system behind the war with the bugs, or the Shadow series following Orson Scott Card's Ender's Game (the original sequels, from Speaker for the Dead on, are not military SF), where the impact of the military on socio-political issues is quite clear.
After this brief rundown of each of the politically relevant sub-genres of Science Fiction, it is worth noting that in many cases a story does not have such an easy classification, and can be read as belonging to one sub-genre or as belonging to another, and that choice (made by the reader) will have an impact upon the interpretation and weight afforded to the issues presented by the story.
Once more I would love to hear your thoughts on these postulates about the different sub-genres of Science Fiction.