OpenID scores a major victory today as Facebook, the largest social networking site in the world, becomes a “relying party” for the log-in standard. Facebook's announcement of full support for the log-in standard is somewhat surprising as it already has what many believe to be a competitor to the open standard in its own Facebook Connect. With 200 plus million users, the social networking site wasn't really in a position where it needed OpenID. This comes as many big names, all of them with a smaller user base than Facebook, only supported OpenID partially and it didn't seem like it was something they actually wanted to do. Facebook took the step nonetheless and the implications for OpenID could be big.

"We've always let our users express their real world connections," Facebook representatives said. "From the beginning, Facebook users could use their college and workplace identities to establish real world networks. Now, they can use open standards to establish their identities on Facebook."

In theory OpenID is designed to make the life of Internet users easier by allowing them to have just one set of credentials across a multitude of sites or services. In practice even more tech-savvy users found it difficult to use. The spotty support it enjoyed from big sites also added to the confusion. OpenID providers come in two flavors; they can be a “relying party,” like Facebook is now, or they can be an “issuing party” like Google, Microsoft, Yahoo and many others. This means that you could use your Google account to log in to Facebook and other services that have full support but you can't use your Facebook or Yahoo credentials on Google.

Facebook seems to be determined to get fully behind OpenID and while it probably won't drive others to change their policy too soon it may get them to consider it. "We've always believed that making the user experience as secure, lightweight, and intuitive as possible, which 200 million people can comfortably enjoy and understand, is one of our top priorities," the company reps added.