Presence is essentially a status indicator -- for now a green circle in your profile picture -- signaling "that you're online and looking for conversation," Haider said. Facebook Messenger and Instagram offer a similar feature.
Haider was clear in pointing out that the features are rough and all about making it "feel more conversational here … still early and iterating."
Initial feedback from the Twitterverse seems lukewarm on reply threating and wary of the presence feature. Users want assurances that they'll be able to turn off the presence feature.
"Knowing when someone is online will have much bigger negative effects than positive ones," user Charles Arthur tweeted in response to Haider's post. "Pile-ons, targeted attacks, all that sort of stuff. Twitter works best because it's asynchronous. It's not your 'friends' like Messenger."