In migrating my web services to a new server, I went ahead and upgraded the OpenID library that parsed.org and my other services use. Now they support OpenID 2 (in addition to OpenID 1), so if your identifier is served by a compliant provider, you can just enter your provider's URL into the input box to make login seamless. For example, myopenid.com identifier users can simply enter myopenid.com into the input box. For other features provided by OpenID 2, (maybe) read the spec.