Actually there's some incorrect information here, Pixar started using ray tracing in films as far back as A Bug's Life. I can't find a picture on line but you c

Actually there's some incorrect information here, Pixar started using ray tracing in films as far back as A Bug's Life. I can't find a picture on line but you can see it in the scene with the glass bottle. That was done by integration with a separate render but since then RenderMan as added support for GI and other ray tracing features. I'm sure this update is significant, and sounds like a ground up reworking of the engine, perhaps replacing REYES? But it's not at all accurate to say the Pixar is moving to raytracing. Pixar has been in that neighborhood for more then a decade.