The update adds several features that Plex users have long enjoyed on other platforms. Here's a rundown:
Plex's software lets you stream video and music files from a PC or certain networked-attached storage drives. Just install the server software and point it to any media folders you want to share, and you can then access that content through Plex's client apps, such as the newly updated Xbox One version. While Plex is popular for watching videos acquired through legally dubious means (such as torrents and ripped DVDs), it has its fair share of legal uses as well.
Unfortunately, the Xbox One app still requires a Plex Pass subscription, which costs $5 per month, $40 per year, or $150 for lifetime access. On most other platforms, Plex lets you buy the individual client app for $5. It's a much cheaper way to go if you don't need the Plex Pass features, such as cloud file syncing, movie trailers and extras, and music videos.
Why this matters: Not all Plex apps are created equal, as each platform tends to be on a different schedule for new features and additions. The Xbox One app, for instance, still doesn't support photo viewing and streaming video Channels, though these features may not be too far off. In a blog post, Plex said it has another update coming soon, as the lengthy approval process for the last update was "harder than killing ice zombies by beating them over the head with an original Xbox console."