I'm going to make a guess here:
Mailman doesn't have a good double opt-in + opt out mechanism. This means that potentially a Black Hat can paste his list of scrapped email addresses into Mailman and send out a metric tonne of spam.
This gets DH's server on the banned list, and creates a mess for everyone.
I would like to have a single list for newsletters and discussion, because I think I can create a better community this way.
I can see several ways to deal with this from DH's point of view:
- Mailing lists have required moderation at least for the first N messages from a given user. When I ran a google group, I moderated all the messages (about 20 per day) because of the list spamming problem.
- Add the opt-in mechanism/opt-out mechanism.
- Limit the number of addresses that can be pasted into the panel interface at any given time. Limit the number of addresses that can be added with a 'subscribe' message in a given day. A limit such as 25 names or 5% of the list size, whichever is larger, would make it essentially unusable for spammers.
- The 'opt-in' email is checked when a list passes a certain size. This prevents someone from composing their spam in the opt-in, adding a million names, and stepping back.
- Count mailing list traffic as part of a customer's bandwidth.
I like having a unified presence on Dream Host. But my announce list is young. If I need to find an alternate hosting system to merge announce and discussion I'll do so.
If Mailman isn't the answer, how about an alternate?
From Spamhaus's page:
"Some examples of software which use COI include Majordomo-2, EZMLM, Mailman, and Lyris."