The upcoming 0.1.0 version of libsixdof has two new features that allow a wiimote to control Google Earth. Firstly, sixdof now supports input through cwiid from a wiimote as a controller. Secondly, there is a tool that can pump events from libsixdof into the Google Earth (GE) window. This way, mouse and keyboard events are delivered to GE when the sixdof controller is used.
Panning would be a lot smoother if explicitl sixdof support was added to GE, but that is probably not going to happen any time soon as the source is closed and Google probably have better things to do than play with wiimotes under Linux ;)