My dad was very much a negatives and print man...started processing glass plates in the 50s, moving onto commercial labs for colour 120 negs in the early 60s. He never really was one for reversal film.
However I've used it on various occasions....having inherited a couple of slide projectors, including a rather wonderful 60s Prinz branded 600W beast, I think it's great fun to unroll the screen, darken the room...smell the burning lamp, hear the fan....and show some slides. I've also managed to process E6 film in the past, whereas I haven't tried C41. I think having the possibility to project directly or to scan/print is potentially great.
As for how much film has been sold....I just hope we help refill the coffers to assist the boys at Ferrania in their work towards producing their E6 films. I'm 100% buying the super 8, and probably some 135....how much will depend on price but definitely buying some super 8.