For Instructors and Admins
Canvas Users ListServ - Open to all Canvas users
If you are interested in joining an established email community who regularly communicate about Canvas usage and feature, please visit https://sympa.usu.edu/wws/info/canvas and sign up! Hosted by Utah State University.
Facebook Canvas eLearning Community - Open to instructors and admins
This is an active Facebook group that is by invitation only, although they will allow anyone that is working as a instructor or admin inside Canvas to join and discuss relevant topics in Canvas.
For the Open Source Community
Open Source Announcements ListServ - open to all Canvas users
If you are interested in joining the open source Canvas users mailing list, please visit http://groups.google.com/group/canvas-lms-announce