: Halo was a story about a secretive alien conglomerate slowly, inexorably
: driving humanity to extinction. There's a definite element of
: fear-of-the-unknown, and a definite element of "Oh, shit, how does
: their technology do that?" A sense of loneliness and isolation only
: enhances that.

: Let's think about the implications of lightspeed-only sensors and
: communication for the UNSC (I imagine that the Covenant has FTL
: communications, but not sensors) during the war.

: When a Covenant ship jumps in-system and lands, say, four light-hours from a
: colony, it will be four hours before the image of that ship's arrival
: reaches the colony. That's four hours to slowly survey the opposition and
: watch outbound flights before the UNSC knows to start the evacuation. The
: images that the Covenant warship is seeing are four hours old as well
: (Younger or older, depending on which part of the system it is surveying)
: but that hardly matters for the Covenant's mission.

: That's the suspense inherent to relativity. If you're operating a sensor
: station, there's a very real chance that the Covenant are already
: in-system, only you can't see them yet. In systems close to the front
: lines, all starships are strongly encouraged to exit on randomized vectors
: before continuing to their destination just on the off chance that a
: forward observer for the Covenant is present.

Yes. I agree.
However, there's also the element of discovering, researching, experimenting with, learning from, and implementing alien technology. Halo started off as you describe, but considering realistically, over time why would it not be possible that humans can learn from Convenant and/or Forerunner technology and improve their own with it? They did with Infinity. So if aliens can presumably communicate FTL or have the tech to do so, why restrict humans from doing so at all?
Again I'm not saying this is overall "good" or "bad", I'm just saying that in-canon, the mechanism exists and it's certainly feasible.

:: If sci-fi is typically an analog for current human culture, then stretching
:: that story across vast distances where communication takes longer very
:: much affects the type of story you can tell. Find a way to way to
:: communicate FTL, and you can tell an analog of a story that takes place in
:: a village, but across the galaxy, and have no communication issues.

: Then you're not telling science fiction. You're dressing up another genre in
: the trappings of science fiction.

This is precisely what Star Trek TOS was. "Gene Roddenberry sold Star Trek in 1964 to NBC as a classic adventure drama, calling it a "Wagon Train to the Stars". But Roddenberry wanted to tell more sophisticated stories, using futuristic situations as analogies for current problems on Earth and showing how they could be rectified through humanism and optimism."

: We need a
: new term, one for a science fiction setting that bothers to think about
: the implications of its fictional technology.

Man vs Technology.
In the science-fiction genre. :P

: Boring, overused, could do with a bit of a shakeup. A space opera set in the
: sprawling, arthritic arms of a human empire that occupies one percent of
: one percent of one percent of the galaxy sounds big enough. Ten thousand
: stars, maybe with a hundred of them sporting a planet or a moon where
: Humanity can drop a settlement.

I loved Firefly for this reason: A believable human future, with zero alien life. Entirely human. If you want science fiction with feasible technology, then I'll toss in - don't include sentient alien life.

Science fiction is more than just technology. It is fantasy. It's Man Vs Something wrapped up in a variety of degrees of technological and fantastical environments, depending on how 'advanced' or future-placed you want to get. Science-fiction doesn't imply any level of feasibility except that it is "fiction" based on "science". Some might argue that if there's any way to conceptualize something Naturalistically, then it can be quantified as science-fiction.

Anyway I'm getting into an area where I may bite of a chunk bigger than I can chew; I'm a sci-fi fan, but not a fanatic ;P and starting to move into a genre discussion that's been debated by people far more knowledgable than I.

Going back to my original point - in Halo's universe, there exists a feasible way for humanity to develop FTL communication. It's not a shark-jumping level of development, but a logical progression, in my opinion, using existing themes and concepts introduced by alien intelligences. That's not an idea unique to Halo, of course, but that does not make it a 'bad thing' inherently. One might not like it, but I'm just saying it's feasible. :)