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

Survival Mode
Removed an exploit from The Construction Site
Fixed issues with Survival Mode medals not being awarded properly in rare cases
Times will no longer be awarded when joining mid-round and cheats had been active during that round

Servers
Server will now reset correctly after all players leave a Versus game


Match Making
Fixed a mismatch between lobbies and servers that will remove the "Server is full" errors when quickmatching
Fixed match making issue affecting Vista64 users
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