Bridging mailing lists to Discourse is something requested by the community since Nabble is no more working for us. The goal is to be able to post from the mailing lists and from Discourse, it is *not* to replace mailing lists.
Guilhem (thanks a lot!) has deployed a test instance that you can find here:
Note: this is a test instance only, if we go in production, all what has been posted in this test instance will be deleted.
The ticket describing how it works:
Category1 and Category2 have corresponding mailing lists where you can post from Discourse.
Category3 is the only one bridged and is a read-only mirror of the list archives. The intention with the two previous categories is to test different bridging methods.
Please help us to test the instance and give your feedback on Discourse site feedback category or in the ticket.