This document summarizes several key features of Silverlight 2.0 including: 1) Web services in Silverlight 2.0 support WCF or ASMX and allow for asynchronous HTTP or HTTPS calls with SOAP, POX, JSON, or RSS serialization. 2) ADO.NET Data Services expose an object model over the web using a RESTful interface with a uniform URL syntax and support multiple representations like ATOM or JSON. 3) Silverlight 2.0 allows for background processing to keep the user interface interactive, isolated storage of local files, and two-way communication between the Silverlight application and host page through calling .NET methods from JavaScript and vice versa.