We currently need to use private boards to illicit feedback from our customers, as we do not want that information necessarily public.
We are using SSO from within our application, but we have many user's users who share the same email addresses (office@whateverdomain.com) etc, on file.
We'd like to allow them to register on the website directly with whatever email address they want to use or Gmail etc, but then require us to approve the account to have access.