Add mailing list descriptions to documentation

docs/source/contributor-guide/communication.md

@@ -37,18 +37,35 @@ We use the Slack and Discord platforms for informal discussions and coordination
 meet other contributors and get guidance on where to contribute. It is important to note that any technical designs and
 decisions are made fully in the open, on GitHub.
 
-Most of us use the `#datafusion` and `#arrow-rust` channels in the [ASF Slack workspace](https://s.apache.org/slack-invite) .
-Unfortunately, due to spammers, the ASF Slack workspace requires an invitation to join. To get an invitation,
-request one in the `Arrow Rust` channel of the [Arrow Rust Discord server](https://discord.gg/Qw5gKqHxUM).
+Most of us use the `#datafusion` and `#arrow-rust` channels in the [ASF Slack
+workspace](https://s.apache.org/slack-invite) and the [Arrow Rust Discord
+server](https://discord.gg/Qw5gKqHxUM) for discussions.
 
-## Mailing list
+Unfortunately, due to spammers, the ASF Slack workspace requires an invitation
+to join. We are happy to invite you -- please ask for an invitation in the
+Discord server.
 
-We also use arrow.apache.org's `dev@` mailing list for release coordination and occasional design discussions. Other
-than the release process, most DataFusion mailing list traffic will link to a GitHub issue or PR for discussion.
-([subscribe](mailto:[email protected]),
-[unsubscribe](mailto:[email protected]),
-[archives](https://lists.apache.org/[email protected])).
+## Mailing Lists
 
-When emailing the dev list, please make sure to prefix the subject line with a
-`[DataFusion]` tag, e.g. `"[DataFusion] New API for remote data sources"`, so
-that the appropriate people in the Apache Arrow community notice the message.
+Like other Apache projects, we use [mailing lists] for certain purposes, most
+importantly release coordination. Other than the release process, most
+DataFusion mailing list traffic will simply link to a GitHub issue or PR where
+the actual discussion occurs. The project mailing lists are:
+
+- [`[email protected]`](mailto:[email protected]): the main
+  mailing list for release coordination and other project-wide discussions. Links:
+  [archives](https://lists.apache.org/[email protected]),
+  [subscribe](mailto:[email protected]),
+  [unsubscribe](mailto:[email protected])
+- `[email protected]`: read-only mailing list that receives all GitHub notifications for the project. Links:
+  [archives](https://lists.apache.org/[email protected])
+- `[email protected]`: read-only mailing list that receives all GitHub commits for the project. Links:
+  [archives](https://lists.apache.org/[email protected])
+- `[email protected]`: private mailing list for PMC members. This list has very little traffic, almost exclusively discussions on growing the committer and PMC membership. Links:
+  [archives](https://lists.apache.org/[email protected])
+
+[mailing lists]: https://www.apache.org/foundation/mailinglists
+
+```
+
+```