Updates to Team Fortress 2, Day of Defeat: Source and Half-Life 2: Deathmatch have been released. The updates will be applied automatically when your Steam client is restarted. The major changes include:
Source Engine Changes (TF2, DoD:S, HL2:DM)

• Fixed a regression in the Mac's minimum system check

Team Fortress 2

• Added new audio lines for Merasmus to use when he attacks
• Fixed a Linux dedicated server crash related to Mann vs. Machine mode