Specify Intranet zone sites in GPO without locking down Trusted Zone sites

Is there a chance we could get a new policy setting that would let admins specify Intranet sites but let users specify Trusted Sites? Is there any chance someone on the group policy team could comment on this?

Many of us are in the situation where we have to configure sites in the Intranet zone, but absolutely cannot lock down the Trusted zone sites.  There would be a revolt if that happened.  There's no way I can know all of the sites my 40 users need to trust beforehand.   And after the fourth or fifth time someone had to call me to investigate and add a new site, I'd be forced to remove the policy.

There are a number of forum entries that discuss mapping sites to zones via GPO, such as

http://social.technet.microsoft.com/Forums/windowsserver/en-US/1aaecbd8-bd85-4145-a153-7015531be2a8/group-policy-for-adding-sites-to-the-intranet-zone

and this one

http://social.technet.microsoft.com/Forums/windowsserver/en-US/3a6d9a15-1fee-4b2b-a18d-0d838f356f2c/alternative-to-site-to-zone-assignment-gpo?forum=winserverGP

It's very frustrating. They get you almost there, and then the cruel reality that you can't do it slips in. (One contains a link which promises the prize, but it's dead).

You can't map sites to zones without locking down all of the site-to-zone assignments.   There isn't a group policy preference for site mapping, only a policy.  (given what GPPs really are, this is a Good Thing). And it covers all of the sites.