I just uploaded a video covering USD Render Prims.
It was made last year to help explain how to use the new Render Pass prim but took me ages to find the time to finish it up.
Hope it helps someone out there!

pixelninja
I think I submitted an RFE last year ... for specifying multiple render passes either explicitly or using pattern matching.
robp_sidefx
Having a separate one for RenderPass-driven RenderSettings selection would still be useful.