Anyone doing email broadcasting knows to be concerned about spam complaints.

You'd think if someone opted in to the list in the first place you'd be safe. Not. The publisher of a popular weekly email newsletter was moved to make this plea:

To flag e-mails as spam when you have asked to receive them just doesn't make sense and it is a singularly ineffective way to unsubscribe.

Even more uselessly, one person has recently reported as abuse the automated message from the list server asking him to confirm his request to join the list. Another, who has tagged the mailings as spam, similarly tagged the message I sent him to tell him that I'd removed him from the list (I suppose it demonstrates consistency, if nothing else).