Silverlight 5 introduced real 3D capabilities via access to a simplified version of XNA. Using this functionality one can build real complex 3D models of triangles, and create vertex and pixel shaders utilizing the full power of GPU to display them.
There are some shortcomings, however, to the new functionality provided. They are as follows:
It is not multiplatform – it will only run on Windows (though it is multi-browser).
If run within a browser, the client will be required to allow the blocked display drivers for that website and this might be a nuisance if you want your 3D animations to be widely available.
The 3D code is essentially not part of the Silverlight framework. It is standalone functionality and the developer needs to spend some extra time and effort in order to make it interact properly with the rest of the Silverlight application.