(Quoted from here)For over twenty-five years RenderMan has been at the forefront of the visual effects revolution, and today RenderMan is a high performance renderer built to tackle the most complicated 3D imaginable. With the new state-of-the-art ray tracing RIS framework optimized for physically-based rendering combined with the efficiencies of the REYES architecture, RenderMan can deliver unmatched flexibility for any production pipeline.
(Quoted from here)Free non-commercial RenderMan will be availabe in early 2015