It's no secret that Google Earth plug-in for AutoCAD has been one of the top downloads on Autodesk lab. This is something Civil users have enjoyed for a few years now, but unfortunately this update was not tested on Civil 3D 2012, so it may not be possible to install it. Today we got a word that Googe Earth Update is now available for other members of AutoCAD family. On top of that we can now import Google Earth image in COLOR (it used to be possible only in back and white), 3D model can now be published to Google Earth, will automatically populate geographic information during publish, image can be draped onto a surface, and other cool things ... and all that while still in AutoCAD. Before installing it check these two links to get better picture of what to expect; read Getting Started and User Guide.
You can download Google Earth Extension Update for AutoCAD on this link: Google Earth Extension on Autodesk Labs.