Silverligth

Improved media support
        Low Latency Audio Playback: Use the SoundEffect API to trigger low-latency sound
        Variable Speed Playback: allows video to be played at different speedsand supports fast-forward and rewind. At up to twice the speed, audio pitch correction allows users to watch videos while preserving a normal audio pitch.
        H/W Decode of H.264 media:Significant performance improvements with H.264 media decoding of unprotected content
        DRM Key Rotation/LiveTV Playback: Long-running live TV playback protected through the use of rotating licenses        Application-Restricted Media: Prevents playback of protected content in unauthorized applications

Improved Text support
* Text Tracking & Leading: Exercise fine-grained control over thespacing between characters and lines in your text
* Linked Text Containers: Create linked RichTextBlocks that allow text to flow seamlessly from one to the next
* OpenType and Pixel Snapped Text :Improved text clarity
* Postscript vector printing: reduces the size of print jobs and improves rendering quality of text
* Performance improvements for Block Layout Engine.

Buildingnext-generation business applications
* PivotViewer -- now included in SDK. Adds support for dynamic client-based collections, XAML-based visuals, and customizability.
* ClickCount: Add supportfor multi-click to your application
* Listbox/ComboBox type-ahead text searching: Listboxes and ComboBoxes can now scroll based on text input
* Ancestor RelativeSource Binding: Bind to aproperty on a parent control
* Implicit DataTemplates: Allow DataTemplates to be defined implicitly
* DataContextChanged event
* Added PropertyChanged to the UpdateSourceTrigger enum
* SaveFile and Open File Dialog: Specify a default filename when you launch your SaveFileDialog and specify a default directory when you launch your OpenFileDialog
* Databinding Debugging: Set a...