With Portal 2 announced earlier today, GameStop has come through with some very noteworthy details. The GameStop site lists the title releasing on October 26, 2010, although we know their dates are always subject to change. However, the most interesting information they give is that cooperative play will be included with this go around in the world of Portal. Here is what GameStop states on their page:

Coming this holiday. Portal 2 is the sequel to 2007's Game of the Year and draws from the award-winning formula of innovative game play, story, and music that earned the original over 70 industry accolades. Features single and multiplayer co-op modes. The single-player portion of Portal 2 introduces a cast of dynamic new characters, a host of fresh puzzle elements, and a much larger set of devious test chambers. Players will explore never-before-seen areas of the Aperture Science Labs and be reunited with GLaDOS, the occasionally murderous computer companion who guided them through the original game. The game’s two-player cooperative mode features its own entirely separate campaign with a unique story, test chambers, and two new player characters. This new mode forces players to reconsider everything they thought they knew about portals. Success will require them to not just act cooperatively, but to think cooperatively.

GameStop has been pretty good to us gamers lately huh...