Interesting that right after j. brought this movie home, I read over at Science Woman's blog that she just viewed it. This is too much of an action movie for my taste, and I never saw Firefly, but it was an enjoyable flick.
There is plenty of human interest, a reasonable amount of romance, and enough humour to go with the space battles and Reaver gore. River makes for some interesting scenes with her ESP and superhuman fighting ability. She really comes through in the beginning with the idea that we don't need to be telling everyone else in the universe what to do.
Notable ideas from the movie:
Shepherd Book tells Captain Mal that it doesn't matter what you believe, as long as you really believe in it, and Mal takes that advice to heart. Now that's right up my current alley of relativistic thinking.
At the end, Mal explains to River that the most important thing about flying a ship is love. Love will tell you when she's hurting and keep her in the air when nothing else will. I don't know if that logic practically applies to spaceships or not, but I do know that it applies to life.
So here's to the power of love.