GPOs are great. They are the heart of Active Directory. One of the things I like about GPOs is their ability to expand and include new settings. For a GPO to expand an ADM file has to be built-this file will include the new settings.
Microsoft released the a document on the subject.
Mmmhhh, ADM files what a pleasure to be able to add registery key changes and other Windows environment settings. But. Creating the *.adm file might be a bit troublesome as I found out after struggeling for more than 4 hours on a basic script. Therefore a posting to guide you in the right direction.
A good reference can be found at http://support.microsoft.com/?kbid=241671
Good luck.