I like the concept of not requiring a site-specific login and password for every site. But I don't feel that OpenID succeeds at this. As a user, I find few site

I like the concept of not requiring a site-specific login and password for every site. But I don't feel that OpenID succeeds at this. As a user, I find few sites that support OpenID and most of those don't work with my OpenID. Login with twitter or login with Google seem popular but tie one in too tightly to a single provider. Mozilla persona (https://login.persona.org/ https://login.persona.org/) seems really promising to me but it is too new to have any good data.