New features to make Reddit look and feel more lively and in-the-moment

I'm always wary they'll use one of these "improvements" (some people may find this useful, I just see it as useless fluff) as justification for killing old.reddit.com. But perhaps that will be the kick I need to finally give up reddit for good.

Wow.

I wonder what are the technical requirements for this kind of real-time user feedback/interaction with the server(s), what kind of infrastructure handles this kind of load, and how it's justified internally considering this (I assume) is new infra and code to maintain, scale, and pay for.