Yes, frustum culling is included. Everything is rendered using VBOs to get a high transfer rate.
One of the features that is missing is hardware instancing for things like vegetation. Another feature that would be important is terrain rendering.
There is very experimental (and slow) support for occlusion culling.
All in all: There is much work to do to get the 3D renderer competetive.
The current system has two different renderers: The fixed function and the GLSL based renderer.
It would be possible (and probably very useful) to implement a deferred renderer as well.
Most of my current work is focused on the script interface and refactoring and documenting the existing engine.