Wave of the future or not, if I were to implement this, then you would all be on your own. I don't use those things to connect to the internet, so I would not be able to troubleshoot, much less see, any problems that resulted from using any mobile device.
As for updating vBulletin, I put that off till there are enough new functions to warrant the expense of upgrading. Custom coding done in the old system normally have to be completely rewritten from scratch in the new system. So I don't take upgrades lightly. Not to mention that normally you wind up trading old bugs that already have work-arounds to NEW bugs that are more easily exploitable by hackers.
Guess I have just gotten set in my ways, but quite honestly I can't comprehend how anyone can see anything on an average website in those little mobile screens anyway. I guess this new generation is going to eventually wind up being called the "squinty generation"....