Realistically and perhaps sooner than you think They are finishing up the LDAP based provider, once that happens, you could hook it up to most company-wide authentication systems.
Once that's working @university.edu and @bigco.com would authenticate directly with the organization. That'll be huge. This is a very very high value feature, I expect it to be the driving force for adoption.
One of the big challenges of large organizations is shutting someone off once they've left the company. This provides very unintrusive way to do so for applications that use Persona. I could see large organizations requiring that all logins use Persona (and the @organization domain).
That's exactly my thinking when creating https://persowna.net/. Providing authentication that hooks up to the corporation's specific system for the entire web is potentially a very big thing.
Once that's working @university.edu and @bigco.com would authenticate directly with the organization. That'll be huge. This is a very very high value feature, I expect it to be the driving force for adoption.
One of the big challenges of large organizations is shutting someone off once they've left the company. This provides very unintrusive way to do so for applications that use Persona. I could see large organizations requiring that all logins use Persona (and the @organization domain).