Hmmm.. Well, to be honest, I haven't used very many forums outside of this one. There are a lot of benefits I'm sure, to upgrading or switching. I like some of the features we have that other forums don't seem to, though, like Visitor Messages and the Forum Archive.
MSPAForum uses VBulletin 4.0.5, and it doesn't seem bad, but no VMs or User Albums there (I assume they might be just turned off due to the sheer size of the forum). It has one feature that I *really* like where it automatically replaces someone's sig if it's over 80px in height
I investigated IPBoard, it looks interesting, shiny. The "Official Board" has some kind of user upload feature (IP.Downloads) that would be awesome for mods, but it costs 50 bucks extra. I see "Social media networks" like facebook-linking features but I might die if the forum ever comes to that. Hopefully that is an optional feature.
Oh, I'm looking through the full feature list. Customizable profile background images? That sounds nifty. Inline popup notifications? Hmm, could be nice, hopefully not as invasive as our current "HEY YOU GOT A PRIVATE MESSAGE" popup (it commandeers focus from whatever else I was doing if the tab was open).
I'm liking some of these features. As long as VMs can carry over (And maybe a suave dark brown forum skin..?
), I think I'd be happy with the change.
Maybe you could make a topic in Forum Suggestions and see what the community at large thinks?