There's something of a debate going on over at the Nature Network as to whether or not the science in science fiction has to accurately reflect reality.
Extremes range from 'obviously not - the F word tells you it's made up' to 'yes, it should, otherwise the public are being led astray.'
Somewhat predictably I prefer the middle ground. I think it's important not to go against the basic tenets of science as we now hold them. I recently watched a Star Trek movie where two ships had collided and one was embedded in the other. The Enterprise went into reverse, and with much creaking and groaning, pulled itself out of the other ship. This is simple violation of basic physics - all that would have happened is both ships moved backwards - and is a no-no.
However, as long as what's written about (or shown) doesn't run counter to everything we know, I see no reason to worry about it. So I have no problem with non-existent nanotechnology, faster than light travel (perfectly feasible, but first catch your wormhole) and time travel, as legitimate scientists have speculated about how all of these could be achieved. I even have no problem with using a 'thrust matrix inverter' and never explaining what this is, as long as the way it's used doesn't involve something that could never even hypothetically be possible.
Anyone insisting on more purity misses the point. Science fiction is speculative. It's pushing the boundaries. It should stretch the mind. And to suggest that science in science fiction should be like science in a real lab misses the point of a novel. I would no more expect that, than expect a crime novel to be like real police work - mostly extremely repetitive and boring.
Fiction isn't a mirror for reality, that's what non-fiction books and documentaries are for. Fiction is more than reality.