What is the difference between the G1 and the ADP1 (Android Dev Phone 1)?
The differences are cosmetic, radio lock configuration, and bootloader. Cosmetic differences consist of the removal of T-Mobile branding and a new etched back design http://android.brightstarcorp.com/images/placeholders/dev3.jpg.
In addition the firmware that comes standard on the ADP1 is missing some of the customization Google and T-Mobile added to the G1. See the following link for details: [http://www.gotontheinter.net/content/android-developer-phone-1](http://www.gotontheinter.net/content/android-developer-phone-1) (However, this isn't a major issue, as the ADP1 can be flashed with any firmware, including the official G1 firmware).