Motorola Xoom one of the few devices that received the official Android Jelly bean update is and perhaps the only tablet except Google Nexus 7 that comes with pre-installed Android Jelly Bean. Now if you have a rooted Motorola Xoom and you are afraid to update to Jelly bean because of losing root, recovery and unlocking your bootloader, then you don’t need to be afraid anymore.
Now there’s a method that will update the rooted Xoom to Jelly Bean and will also keep the phone rooted with the bootloader unlocked and custom recovery of the device. Though you can find several Jelly Bean ROMs with modifications and with some features not working perfectly but this one is an official Android Jelly Bean update. Though the method to install the update is quite simple and easy and it’s almost like flashing any other ROM. Users are just required to download the update and then reboot into the custom recovery, create a backup and erase everything and then finally flash the updated ROM. This method will also update the bootloader and will keep the phone rooted as well with the recovery. Check out this thread for download links and more information.
Source: XDA Developers