- The document discusses issues around allowing non-institutional authentication systems like Facebook to join identity federations and how this affects assurance and trust. - It raises questions about what membership in a federation "club" means and what goals are aimed to be achieved by allowing or disallowing certain members. - It explores how assurance can be provided at the point of metadata registration with a federation and separately for end-user identity proofing at the institution level. Issues around identity assurance profiles are also discussed.