What features are missing from Silverlight presentation markup that will be supported in WPF?
Some high-end Windows specific features of WPF, such as real 3D, hardware-based video acceleration, and full document support, will not be supported in Silverlight. This is by design in order to serve Silverlight’s cross-browser, cross-platform reach scenario that demands a light weight plug-in. That being said, Silverlight will offer a uniform runtime that can render identical experiences across browsers on both Mac OS and Windows.
