I just thought I would chime in that I really liked the serenity movie. It really helped that I had watched the entire season of firefly first though to get an idea of who the reavers were or i would have thought the movie was bad as well since they dont build them up in the movie like they do in the tv series

Also if joss did say this was the end of the firefly series it would be mostly his fault for trying to tie up lose ends from the tv series and not making any new mysteries that would make people want to watch more of the series to find out what happened.
Also it did not help that he killed off 2 of the main characters from the tv series. Also the captain was out of character in my oppinion when he threatened to shoot the whole crew if they did not do as he had ordered.
Really out of sync with my memories of how he would react to similar circumstances in the tv series.
I would love to see more of the series in the future still and dont think joss should count the series out due to him thinking it was not well recieved at the box office. I think he was trying to give to much away at once and the firefly series is better viewed in hour long viginettes where telling the story is a prime factor rather then a 2 or 3 hour action packed episode that reveals to much and ties up all the loose ends and makes no new mysteries.
In other words the movie should not stand on it's own and folks should watch all the previous stuff from the tv series before diving in to the movie.
One more thing I missed in the movie that made it more sterile to me was the inside jokes and comments that they used in the past on the tv series. In some of the old tv series they would make comments about stuff that happened in previous episodes and it made the series more human and feel like their universe was alive since they remembered stuff from past episodes

I would hate to watch the movie without having watched the tv series first as I would have asked myself why did he go back to help that companion girl when he knows its a trap? And who the heck is this sheperd to him anyway as both of them were just there and would only confuse new viewers since theyre past was almost glossed over.
At one point Joss was thinking of putting out a monthly dvd to subscribers on a subscription basis and was asking what the price should be. I think he got the idea from the series called 24.