I saw a question asked on Twitter earlier about what had happened to the 'Material keynote parameter' in Revit 2013. It seems like the Autodesk team were testing us out a bit here in the 2013 version, as the parameter, along with other material information is well hidden away. I've heard quite a few negative remarks about the Materials editor in general. I personally prefered the 2012 setup,.but expect further changes with the release of Revit 2014 next year.