Nice! Lowering barriers to the use of technologies like these is important. Would anyone else be interested in hosting Mozilla Persona? https://developer.mozilla.org/en-US/Persona
I wonder what it's operational requirements are... and whether Mozilla is willing to hand persona.org et al over to a motivated group of volunteers.
Also, Persona was pretty explicitly designed in a way that assumed eventual, native integration into browsers. IMHO, any successor without the backing of a browser vendor would be better served by starting from scratch with a different set of assumptions. :)