I say go see it
What do you say about a movie based on a cancelled TV show that I only watched second-hand on someone else's DVD?

Another season of Firefly might have been better than Serenity, but Serenity might be better than the most recent Star Wars. It was a good movie, not a great one, but the best part to me was being part of the cult. When I walked in the theater I wanted to shout, "Hello fellow nerds." I could feel a familial nerd energy throughout the theater. The laughs were hearty, the clapping sincere. And the post-movie chatter about all things Joss Whedon (you know, the guy that brought you Buffy and various other young girls that kick butt) was hilarious.

Go see it. Me? I'm off to read all of the reviews I've been skipping to keep expectations at a minimum.