Well here's my suggestion along those lines: once they're ready to sell the software, they ought to create a separate board that admins can send their board members to, to test out the software (without disturbing the company site). I think the software will take it from there - it sells itself. People won't fear the change, they'll demand it. Eventually, it'll be the board members hounding the board owners to make the change.
And here's why I say that - I notice this major difference between vB and xF:
With vB, most of the chatter is admin-related, like "oh great a new way to deal with spam!" and "I love the ad integration" and so on.
With xF, most of the chatter is user-related, like "oh wow I love the alerts" and "this quick reply is so easy to use" and so on.
That's why I think this software will be a roaring success: it appeals to the people who actually use the boards.
And I don't think that reservations like "well, it'll have to have CMS" or "I won't buy it without a blog" are going to matter that much down the line. If everyone is drifting to boards that use this software, the board owners are going to buy it.
And I say that with no reason at all to care whether it's a success. I don't know Kier (Kier?) or the other guy (Mike?) and they don't know me, and I'm not in any of the vB cliques (nobody would ever remember me from vB except maybe the guy who spend three days trying to help me with a who's-online problem when I first started there, and I doubt he'd remember me kindly).
I'm just somebody who saw this mentioned on vB, decided to take a look at it because I was bored and had nothing better to do, and ... several days later, I'm so addicted that I'm spending my Sunday afternoon praising software for which I have absolutely no vested interest.