I watched Serenity last night and it was so good I added it to my favorites list. I would highly recommend it except for one problem with the movie, it has some gross scenes. It was written and directed by Joss Whedon, who created Buffy the Vampire Slayer and Angel, so you can understand what type of grossness to expect from this movie. But like Buffy, it is funny and well written; you really care about the characters. The movie is based on a canceled TV show which I have never seen but that didn’t cause me any problem watching the movie because Whedon did a good job filling in the background of the characters.
What I found most amazing about this movie is the fact that it had a pastor-like character (he is called Shepard). Religion is usually absent in sci-fi films, so I thought it was refreshing that there is any reference to God. Whedon appears to understand that religion is not going away just because we have spaceships and sophisticated weaponry. If Christianity has been around for two thousand years it is safe to assume it will be here for thousands more. I think that sci-fi writers make their stories less believable when they exclude Christianity from their futuristic societies.
You can find a more detailed review here