Portal 2's free Peer Review DLC has arrived

Portal 2's totally free DLC "Peer Review" is now available on Steam as well as Xbox Live and the PlayStation Network. Excitingly, the DLC delivers a brand new co-op track! If you don't yet own Portal 2, or Portal for that matter, they're dirt cheap on Steam right now. The official word from Valve with the specifics is as follows.

"If you notice Portal 2 updating today, don't be alarmed: it's only because you're getting the new Portal 2: Peer Review DLC for free. If you don't have a copy of Portal 2 to update, Valve have that covered as well: it's on sale for 50% off through the 6th.

"Peer Review adds a new multiplayer test track for robo-buddies P-body and Atlas, and features a single-player and co-op Challenge mode."