Twitter’s director of product management, Suzanne Xie, has been talking about some new developments the company is planning, and it's related to what it describes as "conversation participants."

Twitter is adding a new setting for “conversation participants” right on the compose screen. It has four options: “Global, Group, Panel, and Statement.” Global lets anybody reply, Group is for people you follow and mention, Panel is people you specifically mention in the tweet, and Statement simply allows you to post a tweet and receive no replies.

[theverge.com...]

Better control of conversations will be helpful, especially where it's a busy chat, so this planned development sounds an interesting new feature.