You cannot upload (except to 3D Warehouse, but that is unrelated), but you can export as .kmz file (containing a COLLADA 3D model) and open it in Google Earth or whatever application you like.
SketchUp’s built-in kmz exporter exports all entities as a 3D model (check also the exporter options button), individual entities will not be mapped to KML entities (like line strings, tracks) that you can edit or toggle visibility with Google Earth. If you want that, you need to try with a KML Tools exporter extension.