I noticed that ESRI added a few more ArcGIS Explorer screenshots
to their site. The images, one of the Washington Monument, one of the moon Europa, and one of the moon Ganymede, reflect a newer iteration of the software. So, ESRI is showing their software's ability to customize the coordinate system--in this case, with various iterations of a planetographic coordinate system.
The navigational controls have been simplified, and additional "Tasks" are visible. By the way, I was told that the "Swipe" tool that I mentioned in an earlier post
is an old ESRI function. The tool allows layer transparency to be controlled interactively.