As fans of Team Fortress, Half-Life, and DotA can attest, Valve always has its customers in mind... as long as those customers have patience in mind.
That's why it's impossible to be upset for the first free DLC pack for Portal 2 having missed its original projected summer release date. Sure, it would've been nice to have some more mind-bending challenges to occupy the time before the wave of holiday releases started, but we can now say that the 'Peer Review' DLC chapter will be hitting all platforms starting tomorrow, so those gamers who aren't pitching a tent for the midnight openings of Rage or Dark Souls can still have something to look forward to this week!
According to Valve's press agents, you, the player, "will continue the story of loyal bots P-Body and Atlas as you puzzle your way through a mysterious new co-op test track and once again match wits with GLaDOS." Exciting! Especially considering that the free DLC for the first Portal felt a bit sterile without our favorite bitchy AI voice rattling our respective self-esteems. The DLC will also include some single-player content, in the form of a challenge mode with leaderboards to tease your friends about.
It's worth noting, given the touchy subject of delays surrounding Valve's content, that the press release making the rounds mentions October 4th as the release date, while Valve's blog says Wednesday. Is GLaDOS making a joke about the Mayan calendar? We shall see! Console gamers should likely expect their access to 'Peer Review' to depend on their respective download service's usual update schedule.
If tomorrow/the-next-day/whenever is too long to wait for you to continue thinking with portals, don't forget the Summer Mapping Initiative contest that Valve put on produced dozens of well-rated community maps, as judged by peers and awarded with awesome Portal swag. And, as we all know, properly motivated subjects produce the best results!