With help from the code ccessex forwarded to me, I actually was able to accomplish quite a bit tonight alone. The main issue is ensuring that every area where topics are displayed has the proper parameters in place so that only users who have permission to view future posts before their post time is reached can view them. There are a lot of specifics to cover, but I intend to make it clean and as feature-filled as possible, with as many options as should be necessary.
At this time, the date or time in the future is specified in any format you'd like on the posting page (different from that one screenshot I posted). You can type anything from "May 16, 2010 10:00pm" to even just "10:00pm" and it will specify the proper time in the future. Currently, I have plans to disable the ability of anyone to reply to a topic that has been posted in the future. The reason for this is because the timestamps of replies get misconstrued and sorting becomes an issue. Still working out some of the issues with future posts that require approval, as well as with updating the "Last Post" information for forums only after the future post date has been reached for a specific post.
All this and more are to be finished by Beta 1. I would expect the first beta to be released sometime this summer, probably anywhere from late June to early July, but please don't hold me too strictly to that estimate. Once the beta has been fully tested and bugs have been fixed, if everyone likes what they see, then I'll ship it off to the MOD DB for validation by my fellow men in purple.
Any other feature requests are quite welcome! Just post them here.