Starting today you can watch your friends’ games with the click of a button via Steam Broadcasting, now available in beta. When you see a friend in game, simply click on "Watch Game" from their profile or from the Steam Client Friend's List to open a window into their gameplay -- no game ownership, special fees, or additional apps required.
The beta is open to everyone on Steam who wants to participate by opting in to the Steam Client beta through the Steam Settings panel. For the time being, concurrent viewing may be limited as the beta is scaled up to support the broader audience.
As always, we want your feedback and ideas on how to make this feature better. Make sure to check out the Steam Broadcast discussions and FAQ, and let us know what you think!