I know that Meetup doesn't really have the features to have two separate mailing lists, one for discussions and one for meeting notices. Since that's the case, I've created a mailing list just for discussions through Google Groups. If you'd like to join, feel free to go to the SBP Group's
site and join. You will need to send a request to join the group (hopefully I'll get around to approving people right away). This is a preventive measure to stop random people from joining and spamming the group.
If you have any questions, please feel free to email me at [address removed].