My big requirement for fiction of any variety is that it have good characters, real characters who hold up on their own and don't just hold up the plot. The characters are a large portion of why several of my favorite mystery series are my favorites (certainly, the mysteries need to be decent, too, but in say, the Margaret Maron series [which, if you like non-doofy women and books that get the South right, you should be reading], the mysteries are really just a back drop for the people.) When the characters start sucking, no measure of good adventure is going to hold that up (which is why I finally gave up the Patricia Cornwell novels, but I still read Janet Evanovich, as the characters [ever so slowly] grow up.) Anyhow, somewhere along the way during my formative reading years (I read anything that wasn't nailed down, including encyclopedias and dictionaries, as a child), I picked up the idea that sci-fi was more about the bright shiny oh nifty tech factor than about the people, and so I never picked up the habit of reading sci-fi. (I'm slowly getting over that; this ramble reminds me that I need to pick back up my Terry Pratchett habit. Then again, he's not precisely sci-fi either, is he?) Now that I have people around whose opinons I trust about books and tv, it's a lot easier to say "I don't like sci-fi, what should I read to prove me wrong?", but it's still easy to fall into the mindset of "I don't like sci-fi" even when you've spent hours in a day watching it. :)
The sci-fi I like to watch is still about people, too; that's why I liked Next Gen, but I'm more into DS9 (it's the "alien of the week" syndrome versus real, in place characters who have to grow because of the setting of the story. There was no contest) and why I love, love, love BSG, because the people are so wretchedly humans (even the cylons? Especially the cylons? And why the hell isn't the show addressing that more?) Anyhow, I'm not sure where this post is going, other than I seem to have caught the sci-fi bug when I wasn't looking, which is interesting to realize.