A few months ago, Valve announced a new technology that would link into Steam appropriately called SteamCloud.  SteamCloud would take all your settings, saved games and other pertinent files in regards to setup of your game, and stores them on Steam.  Now, not only will you have your games available at any computer where you sign in with your Steam account, but your settings and saves will be there as well, eliminating the chore of migrating saved games between computers,

Valve has stated that Left 4 Dead will be the first game that supports this new SteamCloud technology.   The settings and saves for your Left 4 Dead game will follow you wherever you install the game.  Very cool indeed.  Better yet is that the technology is built into the Steam interface, so any game that is sold through Steam can use SteamCloud.  Hopefully more developers will start taking advantage of this cool new feature.

via 1up.com