Last week mixi, the largest social network in Japan, become an OpenID Provider for all of their fifteen-million plus users; one in five Japanese web users are on mixi. While they are another large OpenID Provider -- which some argue is a bad thing -- they are the first large OpenID Provider to also support exchanging profile information. While early adopters using OpenID Providers such as MyOpenID.com, MyVidoop.com, and VeriSign's PIP have had the ability to exchange profile information for well over a year with the Simple Registration Extension, this is an important step forward with larger OpenID Providers seeing the value in exchanging profile information as well. This means that when a mixi user logs in to a site using their OpenID, the site is able to request access to things from their profile like their name. Earlier today, ReadWriteWeb wrote more about how Mixi Brings Sophisticated OpenID to Millions of Japanese Users asking why Facebook isn't using OpenID for their Connect APIs and providing a good overview of why mixi adopting OpenID with Simple Registration is helping to push the envelope:

The moral of the story, though, is that another major social network now supports OpenID and is pushing the envelope with the features included. They aren't acting as a relying party yet, allowing users to login with OpenID from other networks, but the functionality of Mixi user profiles has now increased dramatically thanks to open standards.

Along with mixi's launch last week, Six Apart released a mixi commenting plugin for Movable Type. (Disclosure: I work for Six Apart) This plugin allows mixi users to comment on Movable Type powered blogs and have their name from their profile show up next to their comment. All in all, great news for OpenID coming out of Japan!