Two quick thoughts about this article by Benjamin Plotinsky about Christian allegory in science fiction (via Cliff Pickover's Twitter.) One, Plotinsky is mostly talking about science fiction on screen, not science fiction as a genre of literature. I would hardly consider myself a scholar of science fiction cinema, but as a genre, most of its products are either entirely derivative of sci-fi literature, or not derivative at all in that they are merely more or less thoughtful action movies set in the future or using technology in a manner that's particular appropriate to works on the big screen (for bigger explosions, CGI robots, sweeping space vistas, etc., etc.) For that reason, one can hardly consider sci-fi cinmea to be representative of science fiction in particular, let a lone a stand alone genre, so to write an article that talks about both but at the outset fails to distinguish between them is in my opinion a gross error.
Second, while Plotinsky's article is even-handed it's clear he welcomes Christian influences in sci-fi films in general. But the movie he references are hardly evidence that this trend has done anything to improve sci-fi films. The Matrix trilogy was widely panned for it's completely unoriginal deneoument, where the hero Neo sacrifices himself in an Christ-like manner for the good of those he is trying to save. The new Star Wars films also suffer for Christian influence; the reference to Anakin's "virgin birth" is criticized as being illogical and inconsistent with prior explanations of "the force" in earlier films. And while I'm not sure how much this opinion is shared by fans of the show, I believe that the recent incarnation of Battlestar Galactica suffered greatly from its overtly religious overtones, which were frequently ham-handed and over the top.
Without a doubt there's room for Christianity in science fiction. Try reading someone like Gene Wolfe if you don't believe me. And religion in general has been deeply mined by science fiction authors like Frank Herbert. But science fiction filmmakers have, for reasons that I believe are largely related to the medium itself, failed to handle Christianity or religion in general nearly as thoughtfully or convincingly. It would seem to me that sci-fi films are largely in need of a break from ham-handed Christian allegory.