Through the Google Chrome Release blog, the company has announced a new build of Chrome OS is now available for devices. The updated build is version 48.0.2564.92 (Platform version: 7647.73.0) for those keeping score at home and it is available for all Chrome OS devices. While most updates to the platform focus on performance and security improvements, this update also includes a number of user experience changes and app changes.
Improved Download Notifications
Material Redesign for Video Player
Adding Google Photos as a Default App
Update Recovery Screens
Cultural Institute Wallpapers for Chrome OS
The update is available now and will be pushed to your device in the coming days. I have already upgraded my Acer Chromebook and this update is big. It took several minutes to download unlike most updates which take just a few seconds.
Having worked through the new build over the course of this afternoon (I’m actually typing this on my Chromebook), overall the performance is smooth and trouble free. The new looks to the different areas are nice and certainly make the platform feel a bit more Androidesque versus Chromeish.
In addition to the additional features and functions, there are of course security updates. A big one that is list is  High CVE-2016-0728 Kernel keyring refcount leak with the full list of all the fixes in the update to be released later when a majority of devices have been updated in the field.
To get the update, you can wait for the OTA update or you can go to Settings>About Chrome OS and click the Check for Update button.