Silverlight delivers the richest set of capabilities available to developers today through a Web‐browser plug‐in. Silverlight 5 makes further advances in media, 3d visualization and application development and user experience, adding over 40 new features. The Silverlight 5 Release provides developers their first opportunity to start exploring these new capabilities.
The Silverlight 5 toolkit, downloadable from CodePlex, adds additional features to Silverlight, including the 3d project templates.
The typical developer install consists of the Silverlight 5 Tools (this package), the Silverlight 5 Toolkit, and optionally Expression Blend.
Expression Blend Preview for Silverlight 5
If you've strugged with hand-coding animations, control templates, styling, or other things in XAML, try out Expression Blend.
The Silverlight for Windows Phone Toolkit provides includes open source code, samples and docs, plus design-time support for the Windows Phone platform as well as the Silverlight browser plugin.
The Silverlight 5 SDK is included in the tools installation, but also included here for convenience.
This package contains the MSDN developer documentation for Silverlight 5.
Breaking changes from Silverlight 4 and information on quirks mode and how it enables you to run existing SL4 applications on 5 without issues.
History of the different versions of Silverlight including features and release dates going back to Silverlight 1.