Notes"Google and Yahoo! (and likely Microsoft to follow) are ultimately competing with one another to become the branded single sign-on solution for the web. The good news for users is that by using the same underlying technology, most relying parties will able to turn on support for any new OpenID provider fairly easily. The bad news for users is that since none of the major providers are also relying parties, using services at each of these site still requires multiple accounts. Further, a sign in box with 100 different logos for 100 different providers isn’t a great user experience."FeedUnfurl
SitePoint » The Single Sign-On War Will Ruin OpenID