Did you use 3D or 2D? If your camera does not move, I highly recommend the 2D option, as it renders much faster and you have many options for smoothing the blur. Just change from 3D to 2D, and adjust the Blur sharpness and smooth values to your liking.
Originally posted by PilotLtKettch
and a test render for lighting. does anyone know how to fix the graininess in the motion blur?