I did not like the film ending either. It almost felt like Darabont didn't have faith enough in the material and felt this need to come up with a sucker punch. The Mist is one of my favorite SK works that I've read quite a few times. I remember the first time I finished it thinking: "this would make a wonderful film". Darabont and Rob Reiner are some of the few directors to get SK right in my opinion (and David Cronenberg with The Dead Zone).
The last lines of the novella are truly haunting. Granted, probably not the best way to end a film. And I think the Spike TV series shows a lot of potential.
I have read the book the Mist and saw the Frank Darabont movie. However, recently listened to the audio book on tape. I can not say I was huge fan of listening to the production. It was not exactly someone reading but acting it through audio.
I'm currently reading Skeleton Crew and about two-thirds through The Mist. I have to say that Frank Darabont did a pretty decent job as far as sticking to the original story goes.
As for the ending of the movie, I thought it was the most shocking ending I've ever seen. I was genuinely shocked and it has stuck in my mind since.
I know it's different to the book but, boy, it was a real jaw-dropper in my opinion.
Having finished reading The Mist one thing leapt to mind with regards the ending of the movie and it was the following paragraph
''I checked the gun and then put it into the glove compartment. Ollie had reloaded it after the expedition to the drugstore. The rest of the shells had disappeared with him but that was alright. He had fired at Mrs. Carmody, he had fired once at the clawed thing, and the gun had discharged once when it hit the ground. There were four of us in the Scout, but if push came right down to shove, I'd find some other way out for myself''
In my opinion, Frank Darabont just went with an ending that David Drayton had actually considered for himself in the course of Mr. King's original story and, personally, I liked it.