I posted about this issue on Revit City, and you can import a FBX file from Revit, which can be converted into Sketchup with all materials remaining. I was able to do it through SimLab FBX converter demo. The person who mentioned it opened the fbx file in 3d Max, exported a 3ds into Sketchup, which retained the material properties.
I don't know if there is a free fbx converter or not.
Whatever values or merit Revit, or any other modeling software has, Sketchup has a fantastic quality of moving around a model that none of the Autodesk softwares have.