http://developers.de/blogs/damir_dobric/archive/2010/06/14/microsoft-silverlight-4-tools-for-visual-studio-2010-download-link.aspxThis package is an add-on for Visual Studio 2010 to provide tooling for Microsoft Silverlight 4 and RIA Services. It can be installed on top of either Visual Studio 2010 or Visual Web Developer 2010 Express. It extends existing Silverlight 3 featuresenCommunityServer 2008 SP1 (Build: 30619.63)