Just got around to testing this. Sadly, this only works in a domain environment. I had hoped to be able to use this with a local policy. However when you are setting up the policy these little tid bits of information are displayed:
If this group policy is enabled and the client machine is domain-joined, the file will be processed and default associations will be applied at logon time.
If the group policy is not configured, disabled, or the client machine is not domain-joined, no default associations will be applied at logon time.
If the policy is enabled, disabled, or not configured, users will still be able to override default file type and protocol associations.
I can only hope 8.1 U1 will be the answer.
