I always mentioned about how color grading in Hollywood films and commercials inspired me to do the grading in my photos. Here's is a little video that explain the process. It's not really new video. It's from making of the movie "king-Kong" from KongisKing website. It's done in Weta digital where I am currently working at. After watching that video, you'll have better idea on color grading work flow in films.
Click Here for the video (QuickTime required)
If you're interested more about film making and visual effects process behind the movie like King Kong, you can see more "production diaries" or "making-of" videos in KongisKing site. They are very informative and very interesting.