When Team Fortress 2 launched its Mann vs Machine update, it finally added a co-op mode to the game. Not content to rest on its laurels, Valve had updated the game with several new tweaks and features.
A post on the TF2 Blog spills the details. For starters, the new update includes two more Tours of Duty to sate those who found the first one too easy or too hard. Operation Oil Spill should prove less of a challenge, and Operation Gear Grinder is for those who laugh in the face of danger.
You can also look forward to new Tour-specific loot, including rusty robot heads for Oil Spill, and 24-carat diamond heads for the Gear Grinder. The update also boasts improved match-making, which lets you select from multiple missions. Finally, after a mission is over, you'll be sent back to the matchmaking screen as a group.