Firefly is, to me, one of the best shows ever brought to air. I've watched all the episodes at least several times, which is something that's easy to do, since, as mentioned above, Joss is an amazing writer and director. (Joss contributed to Toy Story and Speed, among others.)
My amazing girlfriend bought me the Serenity DVD for Christmas (even though I don't even celebrate Christmas), and we immediately put it in the player and watched all the way through. It's a big, fun, movie, but honestly, quite a departure from the series. The character of River demonstrates abilities that weren't even hinted at in the series. And I felt like there weren't enough character development in the movie the way the series did so well. But a two-hour movie is obviously not going to be able to do this the way thirteen episodes can do. Adam Baldwin's character is my favourite -- he gets such great smart-alec lines. His "I'll be in my bunk" reaction line will, I'm sure, enter television legend as one of the greatest lines ever.
I question Joss' decision to do certain "big" things with characters in this movie, considering that this movie would be the first time most people would meet them. A "big" or "important" change to a character wouldn't mean much to somebody who's watching the movie but hadn't seen the series.
You'll definitely enjoy the movie more if you're seen the series, but you'll still find enough enjoyment otherwise. Despite what I said earlier, it is, I think, the best of all the episodes. Great, great, great fun, stellar special effects, and without a doubt, fantastic characters, with whom you can really connect and love.
cheers,
supervij
