If you decide to publish a manuscript, do you email, snail mail, or call with an acceptance?
If you decide to reject it, is it always with a form letter?
Does it depend on the manuscript? Does every publisher do it differently?
I always call with an acceptance. If I can't reach the author by phone, I will e-mail or snail mail, in that order.
Rejections are always with a form letter, although sometimes I will add commentary if I have the time and the inclination. If an author gives me their e-mail, that's how I send the rejection. If not, then snail mail.
I do all manuscripts the same. I suppose some publishers will differ, but most of the ones I know call with acceptance. I don't know anyone who has the time to call with rejections.