A new major version of Google Earth doesn't happen everyday, explore the world with tour guide and 3D imagery in Google Earth 7.
From the announcement: "A few months ago, we announced Google Earth for mobile, which offered new ways to see cities in 3D and a new tour guide feature to help you discover places of interest on the go. Starting today, you can get both of those features on a bigger screen that makes it even easier to explore by downloading Google Earth 7 on your desktop. Check out the comprehensive and accurate tours of more than 11,000 popular sites around the world, including our growing list of cities where new 3D imagery is available."

Other recent Google geonews:

Re: Google Earth 7 Released, Google Maps' New Natural ...
Imagery and video here of some of the KML styling and 3D building changes in Google Earth 7: http://goo.gl/qzKts