In the days before Slack and Discourse, there were mailing groups and IRC. We still, of course, have a mailing list (2000+ conversations and 1000+ members) and I'm sure there's still an IRC channel out there, but with the adoption of Slack we've seen a severe drop in mailing list traffic.
Are there better tools than email mailing lists? Sure, I think so. I'm a big fan of Discourse, but I'm not sure adding another tool to the mix will get us all conversing more. Slack has really eaten the mailing list's lunch, and I think that's OK for ephemeral conversation. Because we don't pay for it, there's no permanent history which is valuable to the group. Therefore, I'd like to suggest we converse wherever conversation starts, but decisions are made/published on the mailing list.
I've also mentioned in the past that there are better mailing list services than Google Groups. One I've used to some success is Groups.io and if anyone has other options they'd like to share, I'd be open to exploring them.
Thoughts? Comments?