I've been playing with Google Earth for a couple of days now, and I think it's totally revolutionary. Basically, it allows you to explore a globe covered with satellite-photography images. You can zoom in from outer space, all the way down to where you can see individual houses, and in some cases, individual cars and even people. You can tilt, pan, and rotate to your heart's content, and you can set it to display 3-D images of terrain features and even buildings, if they have the data set for that city.
The building features could use some improvement; it apparently only uses the dimensions of the base and the elevation to generate buildings, so odd-shaped structures like the Gateway Arch in St. Louis or the Luxor pyramid in Las Vegas display as big rectangular blocks.
The photographs used are not always new. Both the Tulsa images and the Oklahoma City images are at least a year old, I'm guessing, juding from structures that hadn't been built yet when the pics were taken. And the quality is variable, so that you can see individual people in the shots of the Forbidden City in Beijing, but can barely make out the white blob that is my mother-in-law's truck in our driveway. And in some places, you can't even distinguish individual buildings.
But still, overall, it's an amazing experience to just revolve the entire planet with a small movement of your mouse, zoom out to see the entire country, then zoom in to look at individual buildings in moments. We've looked at our house, my mother's house, our old home in Clarksville, TN, my old house and high school in Oklahoma City, my old apartment building in Los Angeles, as well as the USC campus. Someday, I'm going to a fly-by of South Korea, maybe the Himalayas. This is one of those things that everyone I've showed it to has not just liked, but enthused about. In a year, it may be passe', or it may be just replace Mapquest as the tool of choice for finding a destination. Whatever it will be, it's a hell of a lot of fun right now.