Earliest ever 3d film uncovered?

Robby Ingebretsen from over at Nerds Plus Art blogged a fascinating piece back in February about possibly the first 3D rendered film to have ever been made.
The animations were made in 1972, and the rendering was done directly to film. The main man behind the work was Edwin Catmull, founder of Pixar

Roberts father, Robert Snr, had kept an original film copy of the animation, which Robert has recently discovered, digitised, and brought to the attention of Pixar and Edwin Catmull.

The quality of the animation is surprisingly good, going beyond simple wireframe graphics and into filled and shaded techniques - even 3d morphing in the opening credits - the mathematics of all for which the team pioneered and developed as the film was made.

The original video, plus behind the scenes work can be seen on Robby's blog entry.