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
Teams that prefer listen servers will no longer be matched with teams that prefer dedicated servers
Official dedicated servers are now preferred when searching for team matches
More populous lobbies are now preferred over less populous ones when searching for games
Players who crash or have failed to load are no longer banned if they have been kicked
Fixed exploit allowing players to end games prematurely using the 'outtro_stats_done' console command
Reduced Dedicated Server max search ping to 150 ms
Fixed a common crash
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