This update is for the SteamOS Beta and Preview channels, and includes new features that are still being tested. You can opt into this in Settings > System > System Update Channel.
General
Fixed an issue where game performance could be degraded after sleep/resume on systems with AMD discrete GPUs
We have just shipped an updated Steam Client to the Preview/Beta channel.
General
Using a physical mouse to click on text input will no longer bring up the On-Screen Keyboard
Steam Input
Fixed regression with rumble on 3rd party SteamOS Handhelds
Improved the styling of multibinding rows in the configuration mapping screen
Remote Play
Added an experimental video codec, Pyrowave, which allows high bandwidth, low latency video streaming. You can find out more on the Steam Remote Play discussion group.