Microsoft's big Xbox One update rolls out today, but don't worry if you don't see it on your console just yet.

"It's important to note that not everyone will get the update at once, as it will be deploying globally to the Xbox One audience," Xbox Live's Larry Hryb wrote in a blog post. With an update this size, you can likely expect a few hiccups. too.

Machines running Instant-On power mode (Settings > Power & Startup) will upgrade in the background when in Connected Standby mode. Those consoles in Energy-Saving mode, meanwhile, will not automatically update, and instead require manual initiation via Settings > System.

Like Microsoft's Windows 10 OS notifications, all consoles not upgraded by Nov. 23 will receive a notification prompting the mandatory update.

First tipped in early October, the free Windows 10-powered upgrade promises "the fastest and most social Xbox experience ever," Redmond said last month.

Players can start and join parties, add friends, and check messages without leaving full-game mode or pausing the action. Also, play an initial 100 Xbox 360 titles, including Borderlands, on the Xbox One for free.

The Backward Compatibility feature begins rolling out today at 3:01 p.m. ET, when players can refresh their Game Collection to see previously purchased Xbox 360 titles ready to install on Xbox One.

Microsoft already announced 104 titles that will be compatible, but plans to add support for 'hundreds more" titles in the future.

Other new features include a Community area to see the latest updates and interact with other gamers by liking, commenting on, and sharing content; a revamped OneGuide for browsing TV listings and trending shows; one-click access to GameHubs for developer updates; and an optimized Store with access to games, apps, movies, TV, and music.

On the Xbox gaming front, Redmond recently rolled out new social features—including a Facebook friend finder—for its Xbox beta app on Windows 10.