Following on the release of a new Dev channel build for Chrome OS, there is now a new Beta channel build too. Build 64.0.3282.101 (Platform version: 10176.54.0) has been released for most devices and can be downloaded now, if you are in the beta channel, by typing chrome://help in the omnibar in the browser.
The update has a laundry list of fixes and improvements that you can read here if you are so inclined. Ultimately there are a lot of general improvements to the platform.
This new build is actually the second Beta channel build for Chrome OS in the last couple of weeks. Being based on Chrome 64, it is likely that we are approaching the end of the beta testing for it and could see it comes to the Stable channel later this month. Chrome 64 is expected to bring significant improvements on how Android apps run on the platform amongst the other security and general performance improvements.
Much like the Dev channel update, it is not recommended that you run the Beta channel on your production Chromebook. There will still be oddities and bugs that pop up from time-to-time and unless you are able to spend time and send feedback on those bugs, it’s best to wait until the release is made available in the Stable channel.