FWIW, a new version has been introduced recently. I'm not sure what changes were made, but the download is pretty substantial, so you would be better off delaying the download until you have a high speed connection.

Minor tip: if looking at mountaineous areas, make sure you have the terrain box checked and set elevation exaggeration (under options) from 1 to 2.

With at least some airlines* now allowing the use of handheld GPS units on planes, it would be great if there were a way for Google Earth to use the (connected) GPS for live flight tracking. While you wouldn't have the internet connection to get full map details, there apparently are some level of the maps stored locally.

*I think this policy has been discussed in other threads, but on a flight earlier this week, I asked the senior UA FA if using handheld GPS in flight was permitted. She went back to check the manual and confirmed that these are now allowed (when other electronics are allowed to be used).