If InCommon chooses to adopt the IdPoLR Working Group's recommendation to help make available an IdPoLR service as soon as possible then UnitedId.org would be a strong candidate. That claim is backed by the following evaluation of UnitedId against the requirements defined in the WG's final report.
Assessment of UnitedId with respect to defined requirements
The near-term solution should initially offer a basic set of identity provider services. The suite of services could grow over time as needs evolve and resources permit. Here is an assessment of UnitedId against the requirements defined above:
UnitedId meets the following MUST requirements today:
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