Yahoo! OpenID: Now with Attribute Exchange! The nice thing about this is that an e-mail address obtained from Yahoo! via attribute exchange has already been verified, so you don’t need to perform the e-mail roundtrip yourself. I expect a lot of OpenID consuming sites will end up with internal whitelists of OpenID providers who they trust to provide verified e-mail addresses, with users of sites not on the whitelist still getting e-mailed a verification link.