Notes:
MailMan – any other systems?
Major difference here is that there is a password associated with the subscription. Password may be generated for you or you may have to choose one.
These days MailMan doesn't seem to generate a password for you. Is this for security reasons?
MailMan sends status messages listing all your subscriptions on a server – very useful! Includes URLs, listnames, usernames. May/may not include the password.