I've been recently generating KML files in Matlab for visualizing "stuff" on the Earth's Surface. It is really easy to generate overlays as well as place "placemarks" showing images. Google Earth is an amazing tool which is going to be around for quite some time. Rather than generating static figures, why not let people interact with your figures? Well, Google Earth seems to have taken care of the interactions.
In addition, if you have lots of data you can use the level of detail capabilities of KML to cut your data up into little chunks. Its just like an octree from you computer graphics class. Pretty easy to code up. All your data can be stored on a server so there is no need to have anybody download it. Its possible to make a webserver emit the .kml files properly and not as ascii so that Google Earth can directly open it.
Once I *finalize* some kml files I'll show simple examples of the Level of Detail visualizations.