One aspect of all this is a provisioning service, one for which Liberty has cooked up a spec. As a user provisioning guy this model of provisioning looked a bit strange to me. Think telephone service provisioning, not enterprise user account provisioning. The funny thing is, I thought there already was a perfectly good provisioning service standard out there - Service Provisioning Markup Language (SPML).
We (Liberty) did look at SPML and plan to use it for the "account provisioning" type of operation in a future specification. However, we also decided that this "model of provisioning looked a bit strange" to try to shoehorn into SPML as the problem we were solving was just different. There was at least one contributor to SPML in the room while this disucssion was going on and the decision was being made, so I presume they also felt that the model was "strange" for SPML.
Historically, Liberty has been very good (if not fanatical) about adopting existing standards where they fit into the solution for problem we were trying to address. This just wasn't the case here.