I agree with Kishi. I only saw the first episode of Firefly, but I didn't even have to have seen that to love this movie. It screamed of "this movie was made for sci-fi fans" rather than the typical "this movie was concocted by Hollywood hotshots to make money."

The characters are all just wonderful characters. I really entirely loved this movie.

(SPOILER)Except when the killed Washburn. He was my favorite character, dammit!