My 0.02 here
XenForo isn't as antequated as you think. It's got a ton of what you're looking for (features needed), and has a much fresher feel than vBulletin , by default. The default template is just great, and editing it is a blast!
I looked at IPB for a while, but the company is clueless when it comes to customer relations. They may look a bit more 'social-y' , but you can honestly do that with XF rather easily as well. It just takes a plugin or three, and it's done
. It really does depend on what you want to do with it.
I agree with the sentiment re: vBulletin. It's antequated. They haven't bothered to keep up with the times, or to update their software in eons. XF seems to be doing rather well though, with a number of updates in the past few months. Yes, it's not as mature as IPB, but that's to be expected. it is much newer.