real-time interactions

 real-time interactions  are the display of interactions on a view of a post (typically on its permalink) as they are received by the post (presumably via webmention), without needing any explicit user reloading, refreshing, or any other tapping/clicking etc.

Typical real-time interactions include:
 * real-time likes (favorites)
 * real-time reposts (reshares/retweets)
 * real-time comments

Aaron Parecki
uses p3k on aaronparecki.com post permalinks to show since 2013-10-13:
 * real-time comments

Pelle Wessman
Pelle Wessman uses A WebMention Endpoint on VoxPelli.com to show, update and remove since 2014-12-07:
 * real-time comments
 * real-time likes
 * real-time reposts

Silo Examples
Real-time interactions are a silo innovation.

Facebook
Facebook was perhaps the first silo to implement real-time interactions since 2012(?) at least, on both post permalinks, and sometimes on posts in a stream or in a collection. In particular, both:
 * real-time likes
 * real-time comments

Twitter
Twitter, as of their mid-2014 front-end redesign, now supports (sometimes) showing real-time interactions on tweet permalinks: Possibly:
 * real-time likes (favorites in particular - seen once 2014-10-21, but then not when window wasn't frontmost, nor when re-activated)
 * real-time comments (@-replies - seen previously)
 * real-time reposts (retweets in particular - presumably since their display is very similar to favorites, yet a retweet on an item that showed a real-time favorite, did not itself show up).