Xenforo isn't held down by a horrid mgmt structure. It's very customer based and very responsive to forum owners needs. This helps give it better flexibility and speed at which it responds to those needs.
If there is anyone that will likely respond (at least in a more competitive and respectful way), it would be IPB in response to how well Xenforo may do. Vbulletin sadly I can see remaining to be the mgmt. clusterf*** that it is right now. It may respond, but if history proves itself, it'll respond in the opposite ways members primarily want.
Honestly, I believe Xenforo will have very little problem winning people over. In the end this benefits everyone though and will force IPB and VB to stand up and take notice to help improve their product lines.
But with this emergence of some of IPB's and VB's biggest coders and graphic designers now putting themselves behind Xenforo, I would suggest putting on those sunglasses because it looks like things are gonna be bright for Xenforo. And I suspect it won't take long for good skins, graphics, and mods to become available. Likely not taking long to rival VB's mod community.
I can all but promise that VB is feeling the heat a bit from all of this.