Ping Identity continues to be a leader in getting product into the marketplace and building an Identity Metasystem. I don't know much about their MedCommons alliance but it looks interesting.
Today at the the RSA Conference in San Jose, CA, Ping Identity announced that PingTrust v1.0 is now available for free download . Previously called PingSTS, PingTrust is a WS-Trust Security Token Service that creates, validates and exchanges security tokens to identity-enable Web Services and to extend federated single sign-on to incorporate Web Services.
Meanwhile at the HIMSS conference in San Diego, CA, Ping Identity and MedCommons announced a partnership to bring standards-based single sign-on to electronic health records. Ping and MedCommons are demonstrating their combined products this week at a HIMSS interoperability showcase sponsored by the Liberty Alliance.