Originally Posted by BMM
Motion capture is used to help animate CGI characters, not create entirely CGI environments. In Avatar, motion capture is used to provide the Na'vi with realistic facial expressions and body movements. Likewise with Gollum in The Lord of the Rings films and The Hobbit.
That's not what it's all used for. Singer even mentioned that they were going to make use of Simulcam technologies. Jeezaloo: