Pretty cool that he's writing his own code to do this (presumably). It reminded me of a neat tutorial for creating grass in Blender:

http://www.youtube.com/watch?v=eshOzshjt90

I created 100% procedural grass using Blender for a book cover recently, and while it didn't have nearly the attention to detail you see in places like Pixar films, the effect was just right for the author's work. I would add that (at least semi-real) shadows are really important for improving the quality of any grass texture.