I would also like to see this—but a bit more comprehensive. What this feature request is all about is putting a group or forum on auto pending approval. Thus, either an entire member group needs pre-approval, or perhaps a forum needs to have every new topic (or every new POST) pre-approved. Also, it would be terrific, simply wonderful, if we could put a member on moderator preview as a punishment, where every new post by that member, no matter where, is set for mod review. This could be a time based or permanent restriction.
Also, it would be fantastic to be able to unapprove a post, or turn it invisible after it’s live.
As an example, I’ll explain how it works in invision power board, the forum I’m most familiar with. IPB has all of this worked out, and on my other forum I have running before I migrated to EE for my future work, it is fantastic. I’ve had several members that I don’t want to ban, but have broken rules or something. I can put them on ten day mod preview (or other length of time), where my staff has to approve every one of their posts for ten days or so…. thus any rule breaking is taken care of before it’s live. If the member keeps on breaking rules, it’s a simple matter to never make the post live, and then you can ban them or something.
Some forums are more sensitive, and the staff wants to control what topics are live. If you have a big forum, the chances are you’ll get a LOT of duplicate topics, which you then have to merge or something. By putting that entire specific forum on topic creation preview only, but not post moderation, you can approve or delete duplicate posts, or merge them in advance.
Or, just say that no one posts to a particular forum without mod preview (say, a rules forum or something where you don’t want clutter, yet it’s important the forum is live).
As for making a post invisible, this has been incredibly useful for things like proposed rules posts I want staffers to chime in on. I can post a rules post, yet make it invisible. Thus, only my staff can see it. They can chime in on it, editing the post, whatever, and it’s all there but invisible to the members. Making a post invisible allows me to also launch a forum with a lot of content already there that I’ve worked on over a few days, but not ready to make public. Perhaps you have a members post that is good, but you just don’t want it available yet—making it invisible can delay a post for a while, and allow you, the staffer, to control more.
How does this work? Well, when there is an invisible post, the forum and topic that contain the invisible post (regardless of source—mod previewed member, staff unapproval, whatever) get a little box or marker that’s in a seperate color, that links directly to the invisible post or thread, or the first one in the forum. This marker is visible to the staff member groups only. So you can click directly on that marker and it takes you to the post.
How is the thread displayed? If you are a member, the invisible post doesn’t show up. The staff assigned to that forum or general staffers see it as if it were visible—but there’s a different background to the post. On my forum, like this one, the background of the table cell containing the post is white, so my invisible posts use a grey background.
I hope this is a bit detailed, enough to see how this can work. 
Thanks for taking this into consideration!
