What is WS-Discovery? As described in this excellent post by Jesus Rodriguez, WS-Discovery is an OASIS Standard that defines a lightweight discovery mechanism for discovering services based on multicast messages. Read the post for an example of its use in WCF 4.0.
“The WCF REST Starter Kit is a set of features, Visual Studio templates, samples and guidance that enable users to create REST style services using WCF. The CodePlex Preview 1 release provides new features that enable or simplify various aspects of using the http capabilities in WCF, such as caching, security, error handling, help page support, conditional PUT, push style streaming, type based dispatch and semi-structured XML support. The WCF REST Starter Kit also provides Visual Studio templates for creating REST style services such as an Atom feed service, a REST-RPC hybrid service, Resource singleton and collection services and an Atom Publishing Protocol service. In addition, there are samples, documentation and other guidance that help to use these new capabilities.”