Improved media support and rich UI capabilities

• Hardware Decode and presentation of H.264 improve performance for lower-power devices to render high-definition video using GPU support.
• TrickPlay 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.
• Improved power awareness prevents the screen saver from being shown while watching video and allows the computer to sleep when video is not active.
• Remote-control support allows users to control media playback.
• Digital rights management advancements allow seamless switching between DRM media sources.

Building next-generation business applications

• Fluid user interface enables smoother animation within the UI. Inter-Layout Transitions allow developers to specify animations to apply when elements are added, removed or re-ordered within a layout. This provides smoother user experiences when, for example, items are inserted into a list.

Text improvements make it possible to build rich magazine-style text layouts:

• Multicolumn text and linked text container allow text to flow around other elements.
• Tracking/leading set precisely how far apart each character is for full creative control.
• Text clarity is improved with Pixel Snapping.
• Text layout performance is significantly improved.
• OpenType support has been enhanced.
• Support for Postscript vector printing enables users to create reports and documents, including the ability to create a virtual print view different from what is shown on the screen.
• Added support for double-click and Combobox type ahead.

Model View ViewModel (MVVM) and Databinding enhancements allow more work to be done more easily via XAML:

• Debugging support now allows breakpoints to be set on a binding, so you can step through binding failures.
• Implicit DataTemplates allow templates to be created across an application to support a particular type by default.
• Ancestor RelativeSource allows, for example, a DataTemplate to bind to a property on the control that contains it.
• Binding in style setters allows bindings to be used within styles to reference other properties.
• The DataContextChanged event is being introduced. Markup extensions allow code to be run at XAML parse time for both properties and event handlers, enabling cutting-edge MVVM support.

Silverlight 5 performance improvements

• Reduced network latency by using a background thread for networking.
• XAML parser improvements that speed up startup and runtime performance.
• Support for 64-bit operating systems.
• Reduced network latency by using a background thread for networking.

Graphics improvements

• Graphics Processing Unit (GPU) accelerated 3-D application programming interface (API) provides rich graphics on the Web for building advanced data visualizations and rich user experience (UI).
• Immediate mode graphics API allows direct rendering to the GPU.
• Hardware acceleration is enabled in windowless mode with Internet Explorer 9.

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:

• Host HTML content as a Web browser control within the Silverlight application. HTML pages, such as help content or e-mail, can be integrated within the application.
• Read and write files to the user’s My Documents folder, making it easier to find media files or create local copies of reports.
• Launch Microsoft Office and other desktop programs. Users can open Microsoft Outlook and create an e-mail message, or send a report to Word utilizing the power of Office.
• Access devices and other system capabilities by calling into application COM components. Users can access a USB security card reader or a bar-code scanner.
• Enjoy full keyboard support in full screen, which enables richer kiosk and media viewing applications.
• Call existing unmanaged code directly from within Silverlight with PInvoke.

Tools improvements

• Microsoft Visual Studio profiling support including CPU, memory, thread contention.
• Visual Studio Team Test support.