During this period processing of unsubscription and other requests will be erratic, probably, and after the move the procedures for getting off the list will change. Details will be posted as soon as they are available. If you don't want to be on the list during this transition period it is probably a good idea to get off immedeately.
Someone sends a message to a list and it gets re-transmitted to everyone on the list.
The answer is that the list doesn't cost anything, of course. Note that there are mostly left-anarchists on the list, but a few libertarians as well. Most of the messages on this list tend to be discussion-oriented, I am not currently aware of any activism mailing lists that are more geared towards information only. As an experiment we're trying to get at least one thread of discussion that is a bit more structured than the normal good-natured debate that is the norm on the list. The idea is that a theme is raised, everyone so inclined thinks about it for a few days and posts an article with their view on the theme.