Google just announced that they have joined the OpenID bandwagon, which means that with your Gmail ID, you could now login to many third party websites with your existing Gmail ID without having to sign up with a new ID, just like what you are already doing with your Yahoo! ID and soon, your Windows Live ID.
However, having said so, Google will still not open their suite of websites to allow OpenID solution and it is still not possible for all these sites to log into each other’s websites and access the various features with the OpenID.
So far, the only benefit of joining OpenID is the elimination of having multiple usernames and accounts with all these websites but basically, the only things they share is login information, that’s all. It will be interesting to see how OpenID transforms and develops as we progress in information technology.