Microsoft’s Scott Guthrie has just announced Silverlight 5 a few seconds ago during his Silverlight Firestarter keynote. Silverlight now support 100% GPU acceleration for video content.
Microsoft has also introduced a new feature called trickplay that allows you to fast playback or slow playback a video or audio content (it’s simiilar to what you natively have in windows Media player). Silverlight also now support remote controls and has better power management.
Continue reading: Silverlight 5 announced: Features breakdown