The Open Geospatial Consortium's current Geospatial Web efforts define standards for delivering 2D map data over the internet. What the Web3D X3D Earth initiative can contribute might be something like a "Web Viewpoint Service" - the ability to query and deliver geospatial data from a perspective other than a 2D bounding box with a zoom function - i.e. the 3D Geospatial Web....
