This poster isn't official art associated with the game. It is, however, totally awesome.
Doug Lombardi, Vice President of Marketing at Valve, recently dropped the release for the first downloadable content pack for Portal 2. Speaking to Kotaku at Gamescom, Lombardi confirmed the pack will become available sometime in Mid-September. Considering earlier claims by the company that the DLC will arrive before the end of Summer, that means we have to wait – at most – until September 21st. No other new details were given. Portal 2‘s first challenge mode DLC will arrive for free on PC, PS3, and 360.
(via 1UP)
And with Valve-time that should be released in about mid October.
Very cool, hope it’s a side story or something for single player.
I think they said there will be some co-op stuff in there, but there could very well be some single player stuff in there as well.