For those being interested:
"Mozilla Persona is an open authentication system that lets you implement sign-in on your site in an afternoon. Today, Persona Beta 2 was released, including a feature called "Identity Bridging" that lets hundreds of millions of users sign into sites supporting Persona with no new username and no new password. The announcement video gives you a good overview of the Beta 2 release.."
See https://hacks.mozilla.org/2013/04/persona-beta-2-launch/
and our https://bugzilla.wikimedia.org/show_bug.cgi?id=34565 and our https://www.mediawiki.org/wiki/Extension:OpenID