BuddhaHB is able to unlock Motorola Xoom Bootloader. He has uploaded a video for this tutorial.
Please Note that this process WIPES all your data. So, remember to BACKUP all the data that you want. Also, this process VOIDS your warranty.
You need to install files for Android SDK and Moto Dev Drivers for this unlocking to work.
Files to install for Motorola Xoom Boot loader unlocking
* Android SDK (ADB): http://developer.android.com/sdk/index.html
* Moto Dev Drivers: http://developer.motorola.com/docstools/USB_Drivers/