Valve have officially announce the first DLC for Portal 2, and will be available sometime during next summer. The DLC will contain newt test chambers, and a new challenge mode for both single and multiplayer modes, amongst other new cool stuff. Valve also said that players should expect more DLCs for Portal 2 in the coming year, and will all be available for the PC, Mac, Xbox 360, and the PS3 and yes they will be free!