There is a great debate in the feature film industry. Where is the line between production and post production drawn? Technology has always been a factor in making films. It limits the types of shots a cinematographer can get. It influences the performance of the actors. It dictates the possibilities of the world a director can create. More and more computers and post production are influencing how a film is shot. This is the first time in the history of cinema where an actor's performance can be manipulated after production is completed. Sure, a skillful editor can use the power of juxtaposition to create multiple meanings from an actor's performance. However, the performance was still, alone, the actor's performance. Now, the performance can be enhanced and changed by skillful computer animators.
An article on the film blog, Twitch (this blog is listed in the blogs to the right) discusses this issue from an audience perspective. I think this is great reading and should get you thinking when and where to use post-production.