To reward everyone for eagerly rushing out to purchase copies of the game, Valve has outlined what it's creatively entitling "Portal 2 DLC #1".
We heard the first details about the content expansion a few days ago, when Valve employee Doug Lombardi confirmed new content would be launching in the summer. Now we've been informed that the free to download expansion pack will include "new test chambers for players, leaderboards, challenge mode for single and multiplayer modes, and more". All gratis, of course.
Valve's still sticking by that rough summer date, but seeing as we're itching for more Portal 2 already, hopefully that's early summer rather than late.