The Mist 8/10
I think this is one of the smartest, best scripted horror movies out there. I think this movie showed how people would really react under the extraordinary circumstances they found themselves in. After the disaster strikes I like how the people in the store drifted in and out of alliances and cliques in a rather - Sartre-esque fashion, until the sides finally coalesced for the final act. I found all the characters believable: Andre Braugher's skeptic with a chip on his shoulder doesn't come off as the horror cliche" non-believer who's gonna get it" - but as someone genuinely trying to work through the situation rationally though his bias against the townspeople clouds his judgement. But the best is really Marcia Gay Harden's Mrs Carmody - the evangelical nutcase. Carmody is a stock King character and a lot of King's written dialogue just doesn't translate well to the screen - But Darabont really gave her some great dialogue and Harden plays it with the just the right amount of zealotry and self-righteousness.
As for the ending - say what you will about the nihilism of the ending, but I look at it this way: I see this movie as a bookend piece with Darabont's other King adaptation of The Shawshank Redemption Whereas Shawshank was about holding onto hope no matter what - The Mist was about hopeless and the events that will drive the everyman to lose all hope.
One more thing - I had the credits rolling as I was listening to the final song on the soundtrack, which was "The Host of Seraphim" by Dead Can dance, I believe. After the song was over, the credits continued to roll, but instead of music you heard the sound of trucks, equipment, helicopters, etc... I thought maybe there would be an after-credit scene, but there was none. I though that was really odd.