well i am goin to throw invision into this mess as from what i have seen invision has pretty much alot of the features of vb but i do think vb probably has more features, but invision is about 2 weeks or so away from releasing 2.0 so you could always check them out. they are free unless you want support from them but there is no need as there is tons of web sites out there about invision board that can help you out. i would say you should check into invision and see what you think.
http://www.invisionboard.com/

ps i have never really messed with vb so i dont know all the features it has but i have looked at the admin panel via there webpage