The Replicant community has several places where people interact together.
Most Replicant developers are on the mailing list, as it is also used to review patches. Many non-developers that are contributors or that don't contribute to Replicant are also on the mailing list.
It's being used for many things:The volume is moderate but there are sometimes spikes due to the to a huge patch set being sent.
To register you can use the Mailman interface . That interface also has a non-searchable archive of the list.
Alternatively, there is also a searchable archive of this list.
Most developers, contributors and many people interested in Replicant are present on the Replicant IRC Channel(s).
People from other communities are also there as we collaborate on various things, like adding support for devices in Upstream Linux.
In practice Replicant has two IRC channels, but they look like one as they are bridged together: You can join any of them and your messages will be forwarded to the other one:This is because an IRC channel was created on Freenode first, but Freenode doesn't allow true anonymous users (if you use Tor, you have to register from a non-Tor IP address first).