Steam Trading Cards are virtual cards earned by playing games on Steam. Sets of cards can be turned into game badges and tradable Steam community items
Collect cards
Play any of the participating Trading Cards Beta games to get trading cards. Up to half the card set is dropped through game play, the other half is earned through your collecting prowess
Craft game badges
Once you’ve collected a set of cards you can craft them into a game badge. Like the current badges, they are tied to your account and are shown on your profile. Unlike the current badges, crafting games badges earns you marketable items like emoticons, profile backgrounds, and coupons. Level up your badge by collecting the set again and earning more items.
Level Up
All badges now have XP which contributes to your Steam Level, a summary of your badge collection. You can view someone’s Steam Level by hovering over their avatar. Leveling up earns you non-tradable items like profile showcases, extra friends list slots, and more
Get rewards for crafting badges
During badge crafting you'll receive random rewards from a set of game related items. They are tradable and can only be used while you possess them.
No teníamos suficiente con tener los juegos para tirarnos horas delante del ordenador, que ahora los de Valve quieren que cuando no estemos jugando también estemos haciendo otras cosas en Steam XD
Estaría bien que lo alguien lo explicase un poco, porque si es lo que he entendido...
¿Echando horas a X juego te dan X cartas que cuando tengas X cartas y X nivel las puedes convertir en X juego?
¿Y cómo/cuándo se empieza?
Aqui hay otro post igual en español : http://www.mediavida.com/foro/juegos/steam-lanza-steam-trading-cards-480490