This is a really interesting library, I'm currently using
OpenSceneGraph (http://www.openscenegraph.org), a C++ scenegraph
library, at my work. However, this library is very interesting.

Can you comment a little more on the vector graphics?  Are you trying
to render vector graphics in OpenGL?  Are graph traversals one of the
areas you've inlined? Or are you doing that in Ruby? ( I guess I should
download it and look for myself :)

- alan