I like a confirmation email to let me know that my signup to their service really did go swimmingly, but I don't care whether it's by a robot or a human, becaus

I like a confirmation email to let me know that my signup to their service really did go swimmingly, but I don't care whether it's by a robot or a human, because I don't read them. The email title "You successfully signed up for Facebook!" gets the point of the message through well enough.