Valve has announced today that the Steam trading cards have now entered into the Beta phase.
“Released in beta today, Steam Trading Cards allows customers to earn Steam rewards for playing the games they love. Those who participate will receive game-specific trading cards that can be collected to earn rewards such as game badges, profile backgrounds, emoticons, coupons, and more.”
The list of participating titles are:
Counter-Strike: Global Offensive
Team Fortress 2
In the later months, the service will expand and more games will be added.