Twitter launched on the Xbox One last fall, and did so with a focus on video. Today, an update adds some new video types, most notably live 360-degree video. Given that just about every platform has been focusing on 360 video lately, so it's not surprising to see Twitter look to expand the places where users can watch it. The Apple TV has supported live 360-degree video for a while now, so it's not a huge surprise to see it arrive here as well.
For those among us with literally no attention span, the app also now supports watching two video streams side-by-side. It's not clear exactly how the audio works in that situation; we're guessing that you can just pick which stream you can hear at any given moment. And if you're a Periscope fan, the Twitter app also lets you browse the "global map" that lets you see where people are broadcasting from at any given moment.
Ultimately, a focus on video makes sense for Twitter on a large screen -- plenty of people tune in to Twitter to comment on big live events. Doing it all from your big TV can be a good way to keep up with the chatter around whatever particular video on Twitter catches your interest.