The team is working thru the planning for this feature and hopes to start implementing soon. I will let you know as I get more updates. Thanks!
302 votesAdam Caviness commented
This is very frustrating. Now, there's a tradeoff here as well. When folks are wasting your time by having a one-to-one conversation within a channel. The argument is they shouldn't be doing that but it does happen. I have found an adequate work around that I think gives the right balance. If you are typing a message in a channel that you want to send a notification to the team over, you type @team and a choice of teams are available in a popup; hitting tab selects the first choice. Our team has agreed to always place @team somewhere in a new topic. Followup responses to that topic probably should not include @team so that each user is not over notified. This works well except of course each user must know and remember the pattern. IMHO, Microsoft should make a new setting for each channel allowing auto-notification of EVERY message in that channel. Other less important channels can probably suffice with the workaround I mention above.
This item is still under consideration by the feature team.