Silverlight 3D Model Importer allows to work with models processed using Xna Content Pipeline inside a Silverlight 5 (beta) project.
It includes all vertex / index buffers data, as well, as textures, bones and mesh / mesh parts info, and provide easy methods to render in SL
In an XNA project referencing a model you can simply do:
var interopModel = InteropModel.FromXnaModel(model);
// and serializes it into a file
using (var fs = File.Create("model.bin"))
using (var writer = new BinaryWriter(fs))
then you can include the created file in a Silverlight 5 xap, and load it using InteropModel.FromBinaryReader().
Silverlight 5 side of the project contains facility methods allowing to render your model very easily.
Models are from the Microsoft XNA samples
An animated Tank
A bump mapped Lizard
A skinned animated soldier
A Battlestar Gallactica Viper with particles