Janrain's hosted (OpenID) authentication service, "handles the UI, authentication, and import of user profile and registration data".
Should take the headache out of delegated authentication – just wondering about possible lock-in.
– Adding RPX to your website doesn't require any changes to your database, and its only requirements are the ability for your servers to make outbound HTTPS calls and to parse JSON or XML.
– When configuring the sign-in interface, you supply a token_url parameter to where the user will be redirected once they have finished the OpenID authentication process. A token parameter is passed to the token_url, which you must extract and pass into the auth_info API call.
– RPX normalizes profile data from our sources into a standardized format (Facebook, Hcard, Sreg…)
– you get the userdata using the token and the back-channel API calls you will make to the RPX servers