Upstream bugs:
* https://secure.phabricator.com/T5358 (setting default email preferences)
* https://secure.phabricator.com/T6296 (specific 'only CC if I'm the author' preference, declined)
https://phabricator.wikimedia.org/settings/panel/emailpreferences/
"A task's subscribers change." : email
This is not appropriate. Especially since voting/following is no longer possible (T88), we don't want users to be scared of cc'ing themselves for the spammy effects of the action. (And yes, they will; we know from experience.)
The purpose of this task is to reduce the amount of emails we send as much as possible.
Solutions:
* (Utopia AKA bugzilla.) Only the reporter should be emailed by default, as in bugzilla. The reporter of the issue is usually interested in knowing whether someone is following/noticing the issue; subscribers already know someone is, them.
* We can remove cc notifications for everyone by default and see how many complain.