What really needs to be said? It’s Joss Whedon. It’s Nathan Fillion. It’s a space western. It’s awesome. Or, to use Firefly speak, it’s one shiny gorram movie. (Also, Glenn Howerton of It’s Always Sunny even makes a very, very brief appearance.)
If you pay attention to the story of how the show was handled, FOX dealt with it all so poorly that it was almost like they were trying to make it fail. Not surprising, it’s FOX.
If you’ve never seen Firefly and Serenity, you should do something about that as soon as you can.