Yeah, since ArchiCAD is leading the poll for most wanted plugin by more than half the votes, I posted a question in the FAQ section asking if it would be unreasonable to expect a AC-Vray bridge any time soon, and one of the forum moderators said that they are keeping an eye on the poll and are certainly aware of AC user interest. He didn't give any hint as to whether a plugin was in the works though; my experience in these third-party developers with development of new plugins for new platforms is that they are heavily driven by user-popularity or user-requests from the respective software platforms.
So while ArchiCAD currently leading the poll helps a lot to try to convince them that AC users would be a viable market for a new plugin, it also wouldn't hurt to actually voice a request in the forum FAQ's as well.
(P.S. - also take some time to drop a vote and a request for a Fryender (
www.fryrender.com - Forum Wishlist section) plugin as well. The more the merrier, I always say
)