As an experiment I went ahead and set up a public slack team with multiple channels to help foster community dialog. If you would like to try it out join us with the link below:
Team Slack Domain: SalesforceCommunity
Direct URL: http://SalesforceCommunity.slack.com
GETTING STARTED:
If you're new to Slack be sure to check out the #slack-help channel once you're in.
Also if you have multiple teams that you're part of and would like to distinguish this team from your others, try out the custom sidebar theme by clicking on Preferences > Sidebar Theme and under "custom theme" paste the following:
Grey Theme
#6c6c6c,#333333,#01a3d6,#FFFFFF,#4682b4,#FFFFFF,#e8673e,#008080
Blue Theme:
#4682B4,#34648f,#28B7E5,#FFFFFF,#28B7E5,#ffffff,#e8673e,#E8673E
UPDATE: Workspace Migrating to "Good Day, Sir!"
Although I still really support this concept and the Slack platform, I never had the time to invest in the community to help it thrive as I imagined (#busyness). With 86 members I'm planning to close the org by the end of the year (2019) and encourage users to join me on the "Good Day, Sir! Community" workspace, they have nearly 1k users and are a very active community with a weekly podcast that continues to spark conversation and healthy community. I really respect what Jeremy Ross & John De Santiago are doing for the community and they've attracted some great contributors, including some key Salesforce staff. Hope to see you there!