So apparently Pixar created Universal Scene Description file format, which is converging on being pretty well used across a variety of 3D products these days. Its lacking in some extraneous functionality (animation - couldn't figure out a common schema; and seemingly a variety of projection approaches/camera descriptions amongst others), but is a solid foundation for converging on file formats. Something the industry has struggled with FOREVER.

Anyhoo, some relevant links:

• Overview
• Geometry - API documentation. Discussion includes supported primitives (eg. for fast collision detection/common representations), as well as mesh, nurbs, etc. and conventions adopted (eg. right hand rule, RH coordinate system for winding)
• Rendering Overview - API documentation. Discussion includes camera setup and pixel ratios