Well that didn't take long. Asus will provide an unlock tool ala HTC that will enable users to unlock and thus void the warranty on their equipment (nothing new there.)
Here is Asus's Official statement
Regarding the bootloader, the reason we chose to lock it is due to content providers’ requirement for DRM client devices to be as secure as possible. ASUS supports Google DRM in order to provide users with a high quality video rental experience. Also, based on our experience, users who choose to root their devices risk breaking the system completely. However, we know there is demand in the modding community to have an unlocked bootloader. Therefore, ASUS is developing an unlock tool for that community. Please do note that if you choose to unlock your device, the ASUS warranty will be void, and Google video rental will also be unavailable because the device will be no longer protected by security mechanism. – ASUS
The good news doesn't stop there. Ice Cream Sandwich will be rolling out to the Prime January 12th so that should make some customers very happy as well.
Asus goes on to say:
ASUS has been working hard to make the highly anticipated Android 4.0 Ice Cream Sandwich available on the Transformer Prime, and today, we have good news for you. Android 4.0 Ice Cream Sandwich FOTA worldwide update for the Transformer Prime will start from Jan 12th, 2012. Thank you for your patience and support through this process. – ASUS
Source: SlashGear