I would venture a guess that autos out sell revolvers but a large margin. I dont know any revolver guys that do not own an automatic but I do know a few auto guys that do not own any revolvers.
That said I can not see the day where there are no more revolvers. Revolvers are still king of the hill when it comes to handgun hunting. Revolvers are evolving in to "big" guns. I own a magnum research BFR in 45/70 and 450 marlin (changeable cylinders) I can not see an auto handling a round like this. Even a round like the 454 casul (big but not the biggest factory revolver round) far out shines the largest factory auto round that I am aware of (50AE)
Shot placement is everything! I would rather take a round of 50BMG to the foot than a 22short to the base of the skull.
all 21 of my guns are 45/70 govt 357 mag, 22 or 12 ga... I believe in keeping it simple