Referencing an earlier comment I made, I got official confirmation from vBulletin that 3.8.x (what we're currently running) will be FULLY supported until 4.1 is available. That means we can stick with what we've got and if it unexpectedly breaks, we can still open "help desk" tickets with them and not get a, "Well, you've got 3.8.x on your forum. We could fix your problem, but you have to move to 4.0.x, instead."
Additionally, while playing around on vBulletin.com, I found that there's another problem that's related to usergroups and that's been confirmed as a bug. While that wouldn't have been a deal-breaker for me (I haven't had to fix our usergroups in months), it's a heavy annoyance.
Finally, while vBulletin has seriously pushed back the 4.0.2 release date, I doubt that the problems I discovered will be fixed, even in that update, because they're concentrating on some bugs they have in Internet Explorer (sorry, Jim, they are). Hey, I might not even bother with the 3.8.5 update, unless there's a major flaw being fixed.
So, what I'm doing is trying to make some improvements, here, that I've been waiting on 4.0.x for: I've uploaded the notehead smilies and got a nice RESIZE BBcode coded. I might upload a few more themes, too.