The the gtx 460 do work, its been confirmed here on macrumors.
Why buy a adapter for 250 dollars when you just can buy the video card
Sorry still confused!! When you say GTX460 works, do you mean with the standard dvi to mini display port or must the GPU have a mini display port or atlona adapter (surely this is the case) The only GPU I have seen with a mini display port is a ATI 5970. Are there GTX460s with min display port?