That's certainly an improvement from before, but I still don't think it's anywhere near ready for primetime yet. The grainy look comes from not enough rays being traced. When the engine can run with significantly more rays, the grain will disappear. That's also why it looks so much better when there's less motion.
One thing I will say is that ray tracing is the future of kickass graphics. It allows for natural reflections (which would ordinarily require framebuffer effects) as well as natural, high resolution shadows, all at little to no additional compute cost beyond what's necessary to do the ray tracing at all. In fact, the only thing that really doesn't scale nicely when raytracing is additional light sources (more lights = more rays).
