In beta starting today, Steam Trading Cards allow users to earn Steam rewards for playing games. The current line-up of participating games is Don't Starve, Dota 2, Counter-Strike: Global Offensive, Team Fortress 2, Portal 2 and Half-Life 2. Users will earn game-specific trading cards that can be collected to earn "game badges, profile backgrounds, emoticons, coupons, and more."
Here's the simplest way we understand it: Create trading Card sets > craft badges > get prizes listed above. There's more details on the Steam Trading Card site.
Leading Gaming Platform Introduces Expansive Player Rewards
May 15, 2013 -- Valve, creators of best-selling game franchises (such as Counter-Strike, Half-Life, Left 4 Dead, Portal, and Team Fortress) and leading technologies (such as Steam and Source), today announced Steam Trading Cards, a new service that rewards gamers for gaming on Steam.
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 group of titles participating in the Steam Trading Cards beta includes Don't Starve, Dota 2, Counter-Strike: Global Offensive, Team Fortress 2, Portal 2 and Half-Life 2. The service will expand over the coming months to include many more titles on Steam.
For more information on Steam Trading Cards visit http://steamcommunity.com/tradingcards/