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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 speeds
and 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 the spacing 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.

Building next-generation business applications

·        PivotViewer -- now included in SDK. Adds support for dynamic client-based
collections, XAML-based visuals, and customizability.

·        ClickCount: Add support for 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 a property on a parent control

·        Implicit DataTemplates: Allow DataTemplates to be defined implicitly

·        DataContextChanged event

·        Added PropertyChanged to the UpdateSourceTrigger enum

·        Save File 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 breakpoint directly in XAML, examine locals, and debug your
bindings

·        Custom Markup Extensions: Execute custom code at XAML parse time

·        Binding on Style Setters: You can now specify a binding within a style

Silverlight 5 performance improvements

·        Parser Performance Improvements: Improved XAML parse times for
UserControls & ResourceDictionaries

·        Network Latency Improvements: Significant performance improvement in ClientHttpWebRequest
scenarios

·        H/W accelerated rendering in
IE9 windowless mode: Silverlight now uses the new
SurfacePresenter APIs for H/W accelerated rendering in IE9 windowless mode

·        Multicore JIT: Shortens the start-up time for Silverlight apps

·        64-bit browser support

Graphics improvements

·        Improved Graphics stack: The graphics stack has been re-architected to add features such as
Independent Animations

·        3D: Use the XNA API on the Windows platform to gain low-level access
to the GPU and draw vertex shaders and low-level 3D primitives. Includes Render
targets, XNA built-in effects, surface composition settings for depth/stencil
buffers and multi-sample anti-aliasing

Silverlight 5 extends features of the "Trusted Application" model

Silverlight 5 extends features of the
‘Trusted Application’ model to the browser for the first time. These features,
when enabled via a group policy registry key and an application certificate,
mean users won’t need to leave the browser to perform complex tasks:

·        Multiple window support: Launch multiple top-level windows inside a SL OOB application

·        Full-Trust in-browser: Using Group Policy, deploy signed in-browser applications that
harness the full power of full-trust functionality

·        In-browser HTML support: Host your WebOC within an in-browser SL application

·        Unrestricted File System
Access: Read from and write to any directory on
your system, from a full-trust application

·        P/Invoke support : Allows existing
native code to be run directly from Silverlight

Tools improvements

• Visual Studio Team
       Test support.