WCF RIA Services will soon be rereleased under the Apache 2 license as Open RIA Services. In preparation for this some functionality is being dropped from Visual Studio 2013.
LightSwitch brings together a number of technologies including Silverlight, Managed Extensibility Framework, and WCF RIA Services. If LightSwitch becomes popular, developers who understand these technologies will have a significant advantage over those who simply wire forms together using the design surfaces.
Silverlight 4 was released back in April without essential development tools.Recently it was announced that Silverlight 4 Tools for Visual Studio 2010 is ready. In addition to basic Silverlight 4 support and templates for RIA Services, there are many IDE enhancements to make working with Silverlight, WPF, and XAML easier.