Valve announced at a Thursday press event Steam Cloud, a feature that will let Steam users access not only their Steam games from any computer (that feature is already available), but also "game-generated data" such as save games and configurations.
Steam Cloud will be rolled out first in existing Valve titles Half-Life and Half-Life 2. Counter-Strike will soon support the feature, and the upcoming Left4Dead will ship with it.
All of the data will be transferred to Steam's back-end once users connect to the service.
Other game-generated data that Valve intends to store includes deathcam screenshots for Team Fortress 2 and recordings of games.
Other "near-future" Steam additions that Valve revealed today include driver auto-updating, a system requirements-checker, new community calendar functions, "official" communities, localized pricing (i.e. not just USD), recommendations, a shopping cart and more payment methods.
Valve's "Steam Cloud" Materializes : Next Generation - Interactive Entertainment Today, Video Game and Industry News - Home of Edge Online