Updates to Team Fortress 2 have been released. The updates will be applied automatically when your Steam client is restarted. The major changes include:

Engine (CS:S, DoD:S, TF2)
Fixed clients locking up while attempting to load the game and re-enabled signature checking

Team Fortress 2
Fixed a case where some items would display an empty string for their name
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Updates to Left 4 Dead 2 have been released. The updates will be applied automatically when your Steam client is restarted. The major changes include:

Left 4 Dead 2
Dev Choice Mutation: Follow The Liter
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Updates to Counter-Strike: Source Beta have been released. The updates will be applied automatically when your Steam client is restarted. The major changes include:

Counter-Strike: Source Beta
Fixed a bug where the player crouching/standing animations were delayed until after (from the player's local viewpoint).
Changed the way that scope zooming works so that it is no longer affected by client-server latency, and zooming begins immediately for the local player. This fixes an issue that would g... [read more]

Alliance of Valiant Arms (PC)Popular multiplayer online first-person shooter offers new co-op mode in recent update.
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Updates to Team Fortress 2, Counter-Strike: Source and Day of Defeat: Source have been released. The updates will be applied automatically when your Steam client is restarted. The major changes include:

Source Engine Changes (CS:S, DoD:S, TF2)
Disabled signature checking to determine if it's the source of some reported launch issues
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Updates to Counter-Strike: Source have been released. The updates will be applied automatically when your Steam client is restarted. The major changes include:

Counter-Strike: Source
Fixed a crash that could occur if a player disconnected shortly after attacking a bot
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Updates to Team Fortress 2, Counter-Strike: Source and Day of Defeat: Source have been released. The updates will be applied automatically when your Steam client is restarted. The major changes include:

Source Engine Changes (CS:S, DoD:S, TF2)
Disabled clients loading server plug-ins unless the plug-ins are signed by Steam or the client is running in insecure mode.
Added a checkbox to the Options->Audio dialog to control muting the audio when the game window is in the background.

Counter-Strik... [read more]

Updates to Left 4 Dead 2 have been released. The updates will be applied automatically when your Steam client is restarted. The major changes include:
Dev Choice Mutation: Hard Eight
Fixed a remote DLL loading exploit (MS KB2264107).
Fixed a crash when disconnecting a rcon connection due to an invalid password when multiple sessions were already connected.
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Updates to Left 4 Dead have been released. The updates will be applied automatically when your Steam client is restarted. The major changes include:
Fixed audio client concommands that could lag a server.
Fixed a remote DLL loading exploit (MS KB2264107).
Fixed a crash when disconnecting a rcon connection due to an invalid password when multiple sessions were already connected.
Get the full article at store.steampowered.com

Medal of Honor (PC)Army and Air Force Exchange Service won't sell the game this fall.
Get the full article at ign.com