Updates to Left 4 Dead have been released. The updates will be applied automatically when your Steam client is restarted. The major changes include:

Left 4 Dead

• • Made the variable "mp_gamemode" available again. Note that you can also load maps directly with different game modes by specifying it in the map command. For example, "map l4d_garage01_alleys versus" will set mp_gamemode versus for you automatically and load the first map of Crash Course
  • Added "mm_dedicated_force_servers" to allow specification of a list of dedicated server addresses manually used for searching (ms_force_dedicated_server is depreciated)
  • Updated shared libraries and DLLs preventing dedicated servers listing correctly, appearing on Steam groups, and being found via sv_search_key
• A new campaign, "Crash Course", is now available for play in Campaign, Versus and Survival modes
• In Versus mode, all weapons, pills, health packs, molotovs, pipe bombs and other items will now be identical for the second round of a chapter
• Matchmaking has had several improvements to make finding and joining games even faster
• Ten all new "Crash Course" achievements have been added

Crash Course delivers new single-player, multiplayer and co-operative gameplay and bridges the storyline between the No Mercy and Death Toll campaigns in the original game. To celebrate, we are offering Left 4 Dead at 50% off for 3 days. Or share the fun - get the Left 4 Dead Four Pack and give the game to your friends.

While containing both Survival maps and a Co-operative Campaign, the primary goal of Crash Course is to deliver a complete Versus mode experience in just 30 minutes, resulting in a streamlined version of the game's existing Versus campaigns.

Learn more about the free, all-new free Crash Course DLC on the Left 4 Dead Blog.