But now I see the the jist of the idea implemented.
Next providers are added to the list based on the estimated number of users they have, for example Yahoo and AOL have many users and will likely always be in the list.
And isn't this a sort of 'preemptive whitelist'?
Relying Parties may then manually add your provider to their ID Selector from the configure page.
Rahter than filter out OPs at authorization time, filter them at selection time.
Darwin would love it.