Sure, but if the question is between medium value sites leaning on sending emails to control accounts and medium value sites leaning on persona for identity assertions, there aren't really any new issues, and all those people get rid of some passwords. It doesn't solve your problems, but it doesn't make them significantly worse and it is a step forward for most people.

(I actually think the use of an email address in persona is genius, anybody who wanted valid email addresses would never consume something like OpenID)