The Liberty Alliance released phase 2 of their work on identity federation. The latest installment is called the Web services framework, ID-WSF (complete list of documents). ID-WSF provides a framework for identity-based Web services in a federated environment. There will likely be some conflict on this between the work of the Liberty Alliance and the WS-I framework proposed by Microsoft, IBM, and others. Liberty adopted the WS-Security specification after it was turned over to OASIS (although there's reason to argue that even that isn't enough). Liberty hasn't adopted WS-Federation, however and last month, published a white paper comparing their approach with WS-Federation. Liberty refuses to adopt standards like WS-Federation unless they're turned over to a standard's body. I think that's wise.