Updates to Left 4 Dead 2 have been released. The updates will be applied automatically when your Steam client is restarted. They will be coming arriving with an upcoming title update on the Xbox 360. The major changes include:

Left 4 Dead 2
  • Changed Survivorbot item hunting behavior
  • SurvivorBots now stay closer to human players in all game modes
  • Fixed Survivorbot navigation issue in The Passing: Riverbank
  • Fixed bug where a SurvivorBot could become catatonic when attempting to save another Survivor from a Smoker
  • Fixed condition where SurvivorBots would not enter the saferoom
  • Increased self-inflicted friendly fire damage from the Grenade Launcher
  • Fixed bug where the M60 would reset its ammo if dropped in certain situations
  • Car Alarms will now trigger anytime a Special Infected pushes/pulls/rams a Survivor into an alarm car. This change only affects game modes with human-controlled Zombies