I have this weird problem when i try to import skp-files in the latest Rhino 5 64-bit (5.1.20808.315, 08-08-2012).
I created the model in Sketchup set to millimeter and when I import to Rhino (also in a millimeter template), the model is downscaled with some inch-ish factor (please see the attached screenshots). Although the Distance command still measures in millimeters.