See also Users/Mentice.
OpenSG is used for 3d visualization in a growing set of endoscopic procedures, complete with haptic feedback. We have layered a set of C++ objects on top on OpenSG to provide full xml-scripting/configuration. In addition, we heavily use shaders, GLSL, FrameBufferObjects, etc to provide the required visuals. The haptic & physics thread run between 300 and 2000 Hz (depending on configuration and load), the visalisation is around 100 fps with vsync off.
In 2005, we chose OpenSG out of several other popular (commercial and free) scene graphs when starting a new project with a _large_ portion of research and unknowns, mainly because of features, support (user base) and not least clear and concise design. OpenSG did not fail to meet up with our demands and continues to prove it to be a very successful choice. /MarcusL