A promised feature for tvOS 10, single sign-in for cable companies, is not available yet and is listed as "coming soon" on the Apple TV page.
The single sign-in feature revealed at the 2016 WWDC will ultimately allow users to enter a cable company's login information once, with automatic propagation across all installed apps that support the feature. It is not known if the feature was slated for launch, or if it was planned to appear in a "point" update to tvOS.
Currently available in the tvOS 10 release is dark mode, and Siri enhancements similar to that in the iOS 10 release.
The tvOS update is available for fourth generation Apple TV owners, through the Apple TV itself.