The way I figure it, the minimum number of people you need in any traditional production is essentially the cast and base operators (which could also be cast members if multi-skilled)

However if you go into 3D animation, this number can actually go down - to the point where you have a content production team around the size of a small startup.

The model I'm looking at could be described as a digital aniation studio, a "mini pixar" if you will, that uses open source software (Blender, Cinelerra) and homebrew motion capture (both facial and performance) to get performance across in a quick manner and using a significantly smaller team. I'm also looking at leveraging EC2 for rendering instead of investing in purchasing multiple servers for a render farm.

The model isn't scalable across the entire film/tv industry of course, but I figure it could work for a couple studios and this is what I'm working on trying to prove right now.