This guide includes all you need to know about it from a user's perspective.
The same release being deployed at https://is.test.wso2.org for the purpose of RSA Interop tetsing - which also demonstrates the functionality of WSO2 OpenID Provider.
WSO2 OpenID Provider interoperates with Blogger and Yahoo OpenID.
Please note that your OpenID obtained from https://is.test.wso2.org will not last long, since the server can be reset. Please use this as an demonstration and to work on interop testing.