The X3D import in Blender 2.74 is rather limited. We've expanded it to support a larger subset of the standard.
All the code changes are in import_x3d.py , and it should go into C:\Program Files\Blender Foundation\Blender\%VERSION%\scripts\addons\io_scene_x3d (on Windows) or into /usr/local/blender-$VERSION/$VERSION /scripts/addons/io_scene_x3d (on Linux).
I've been going by the standard as outlined here: http://www.web3d.org/documents/specifications/19775-1/V3.3/index.html . When not sure, I'd compare to a reference implementation, X3DOM ( http://www.x3dom.org/ ).
- all geometry nodes from Rendering
- all geometry nodes from Geometry3D
- ImageTexture (including primitives)
- TextureTransform (needs careful testing)
- all lamp nodes from Lighting
The UI was left intact from the existing implementation.