Steam News announces a free weekend is underway for Red Orchestra 2: Heroes of Stalingrad, celebrating the recent release of the free Fall 2012 content pack for the World War II shooter sequel. The weekend runs until 4:00 pm EST and the game is on sale for 75% off until Monday at 1:00 pm EST. The announcement we received about this also mentions double XP, but that's not mentioned elsewhere in the announcement, nor is it mentioned on Steam, so we can't say whether an XP bonus is in play or not.