When Verizon launched the Motorola Droid, the most compelling feature was the Google turn-by-turn navigation acting as an internet-connected GPS system with voice guidance and automatic rerouting. The feature was only available on Android 2.0 that only exists on the Droid.
Today, Google announced the same feature Google Maps Navigation will be available to devices running Android 1.6 (Donut) and higher, such as the T-Mobile myTouch 3G and the G1.
This release also includes the new Layers feature, which lets you overlay geographical information on :the map. View My Maps, transit lines, Wikipedia articles about places, and more a la augmented reality.
US Android 1.6 users can download an updated version of Google Maps from Android Market to use Navigation today. Google Maps Navigation is in beta and is currently available in the United States.
Some features of Android 2.0 are not available on Android 1.6, for example, the ability to use the "navigate to" voice command. However, you can still create a shortcut that will allow you to launch Navigation and start getting directions to a specific place from your current location with just a single touch from your home screen. For example, you can create a "Home" shortcut to quickly navigate home, no matter where you are. Just use the "Add" menu item from the home screen, then choose "Shortcuts", then "Directions."