I just found out about this exporter to Google earth from one of Autodesk's products. Maybe this means that all of their products will offer this soon in response to SketchUp: "The Autodesk® Civil 3D® 2007 Extension for Google Earth™ - Technology Preview is the first Google Earth publishing tool designed to specifically meet the needs of Civil Engineers and Surveyors. Using the easy-to-use, wizard-driven interface, you can publish intelligent Civil 3D objects and metadata including points, parcels, alignments, corridor models, surfaces, and hydraulic networks directly to Google Earth in seconds." http://usa.autodesk.com/adsk/servlet/index?id=7294687&siteID=123112&linkID=3549304