We’ve been working like mad to get Silverlight v1.0 ready to ship.  We’ve improved perf, added a small set of features and fixed over 600 bugs since the MIX ’07 beta was released.  The RC will be publically available very soon, but to prepare, Tim Sneath has posted a preview release of the RC SDK that my team put together.  This .zip file not only contains the newest silverlight.js and Visual Studio templates, but it also has the doc containing breaking changes and what’s new since the beta.  What is new since the beta you ask?

• New "root" property on Content. Enables access to the root element of the XAML DOM.
• New “Tag” property on UIElement Enables user storage on every Silverlight UIElement.
• New MediaElement APIs for selecting different audio streams out of a file with multiple audio tracks. See the AudioSteamCount and AudioStreamIndex properties.
• Improved media performance: optimized assembly instructions for the video decode.  Applies to both Windows and OS X
• Media script commands encoded in a separate stream in the video file will now raise the MediaElement’s MarkerReached event