Mailing Lists
E-mail is used for asynchronous and recorded discussions. Those should typically be most of the discussions as people have varying time zones and commitments.
We use several mailing lists. The debconf-team list is used for the general organization of the conference. You can post a message to each mailing list using its address. You can also subscribe to any of the public lists to receive messages posted there. You do not need to be subscribed in order to post, but without subscribing you may miss replies.