I have been thinking about this myself.
I think the obvious point is it is too simple to convert a color photography into b&w. Most say "Hey b&w is so wonderful" but they would not like to have a camera that cannot also do color (and video and and and...). The quality difference (because one would not have a Bayer filter) is not too relevant. I have b&w converted shots from my D700 (11 MP "only") that are sharper than b&w film.
Today, who would buy a telephone that does not take photos or a radio that does not show the time or a wrist clock that does not measure the puls. I am sick of this but it is how people think.
Even if you like landscapes, why not also have a fast motor drive and flash build in - maybe I will need it some time. So, to buy something that is not fully equipped for everything that may come handy once in ten years - impossible.
To me, the strong thing with b&w film is that I know I am set to b&w. The alternative is the MM, which is too expensive.
But by the way, I would not buy a b&w D610. I do not need the build-in flash :angel: