I know this is an old thread but I felt like I should revive it.
I learned more about gaming from RPPR than anywhere else, my characters are more interesting, I go out of my way to roleplay with NPC's because they are people too. I learned to use my role as GM to collaborate with my players rather than to tell them a story. I have used that lesson to try to make my friend a better GM but he still insists that we are playing "his" game. Alas, no wonder no one wants to play "his" games anymore and they are always asking me to run things.
Also after reading this thread, and speaking from experiance. I think Ross has sold more people on CoC than Chaosium could have if they spent thousands on marketing.