As my recent note mentioned, the plan is to have an UMA WG "technical" call this Thursday. I'd like to discuss the RAR/PAR specs particularly, since we haven't fully yet, and catch up on XYZ. Here is the previous thread discussing RAR, and here is a handy IETF 106-related blog post with relevant spec links. (I attended the TXAuth BOF session remotely and plan to dial in to OAuth session 1 tonight.)