Ability to 'subscribe' to specific types of conversations.
1. Item type: Story, Epic, Feature. For example, the Product Strategist probably doesn't need to know about conversations at the Story level.

2. Project, Team, other: Perhaps I only want to get emails about teams I am involved with at the Feature level. While I may be interested or curious about other teams' Features, I don't need a flood of emails about them.

Earlier today, I added a conversation to a Feature to make note of something we discovered/decided that needs to be brought up to Portfolio Mgmt team. I did not mention anyone in it (it was more a note than a conversation, but there is no Note field). I discovered that a bunch of people got an email about the conversation--that was not my intention.