Actually, some of the latest generation of "mirrorless" d!git@l cameras have interchangeable lenses with very short registration distances. That makes it fairly trivial to make adapters for older manual lenses and I see lots of talk about people doing that. No doubt some will adapt because they already have lenses in hand. I don't have any idea whether the number of people using those cameras deciding to run out to acquire such lenses would represent a visible bump in demand. I think a lot of those cameras are acquired to use as high end P&S.
(Time will tell!)