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

Left 4 Dead
Lobbies and games you've recently joined and left will be ignored for two minutes. This will prevent a player from ending up in the same lobby or game when quickly searching for another
Restored Find a Game Lobby/Find a Game in Progress to the Create Lobby screen available from the Lobby Browser
Updated localization text
Fixed an issue where VPK.EXE would not extract all files
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