@dalias yeah, but without passing through a screen name, it was less convenient to use than passwords.
LID (which preceded OpenID) had all of that and more, but that data got dropped in a byzantine standards process that destroyed the necessary functionality to make it convenient.
Which is why I implemented LID on my blog, and a YADIS (part of OpenID) reference (for Verisign), but when OpenID came around I said "meh, not gonna bother".