The Gingerbread update brings HD 1080p video playback, an enhanced and simpler home screen and an update user interface. Developer’s and fans of rooting phones will also be pleasantly surprised that this update unlocks the boot-loader. Both HTC and Motorola have recently come under fire by the development community for having locked bootloaders and quickly changed their position. Motorola recently responded to developers by saying they would release phones in the 3rd and 4rth quarter with unlocked bootloaders. They made no reference to going back and unlocking the bootloaders of previously released Android devices.
Gottabemobile has reported they’ve tested the AT&T build of Gingerbread and the unlocked bootloader is definitely there. To find the update go to settings>About Phone> update