As promised Asus has released the much-awaited bootloader unlock tool for Transformer Prime tablet. Available for download now at Asus support site, it unlocks the bootloader of Transformer Prime TF201 running on Ice Cream Sandwich. So, if you are still on Honeycomb, you will need to update to ICS to get the benefit of this tool.
After unlocking the bootloader of your tablet, you will be able to flash custom firmwares on the device. But you should keep in mind that unlocked Prime tablets will not be covered under warranty and also won’t get official updates. You will be able to read full statement from the company at the source.