From splatterfilms, who got the vid from IGN.
This particular "Mist" trailer was released on the Internet only. You can see more Mist Trailers at yahoo: http://movies.yahoo.com/movie/1809834165/info.
Stephen King's The Mist is directed by Frank Darabont and stars Thomas Jane, Marcia Gay Harden, Laurie Holden, Andre Braugher and Toby Jones. Release date: November 21.
If you like little bugger creatures that like to kill humans, you should like it.