I'm currently running a vBulletin powered site, with a Mediawiki database bridge for the wiki. You can see the site in operation http://www.gaminglove.net/
I've been growing increasingly frustrated with both of these platforms, and have tried to use a premium vBulletin wiki plugin to have the wiki be a much more integrated part of the site than it currently is.
That of course, proved to be a mess, with the import not functioning correctly, crucially, it killed every single essential template being used on the wiki, so for the moment, it's installed, but not being used.
I also own a vBulletin 4 powered site (including the "CMS"), but the vB 4 branch is a joke, the CMS is lacking crucial functionality that I want, and vB4 styling woes are relatively well known by people interested in forum software.
With the release of Drupal 7 looming, I want to look back into rebuilding the site. That, of course, comes with a few crucial caveats:
I need a good forum, average posts per day on the site are relatively low, but I need good admin controls. I'm not entirely convinced that AF in it's current implementation is a suitable alternative.