Citation:
Steam Client Update Released
December 14, 2004, 10:57 am · valve
A platform update is available and will be applied automatically when Steam is restarted. The changes include:

Steam

* Source MODs will now automatically appear in the games list
* Improved startup process for Steam
* Fixed crash when creating a backup that would span multiple DVDs
* Fixed a bug that would unnecessarily validate Steam caches after a cache corruption
* Fixed Condition Zero: Deleted Scenes and Codename Gordon failing to backup correctly
* Fixed a bug where the message “the game files will be deleted and re-acquired” would repeat
* Fixed offline mode failing after not connecting to Steam for more than a month


Half-Life 2

* Optimization to the Steam filesystem to reduce game launch and level transition time


Source SDK

* Simplified debug-launch process for MOD developers. MOD developers no longer need to place a config file in their directory
* Added a registry key for MOD developers to use to locate a user’s Steam installation located at HKEY_CURRENT_USER\Software\Valve\Steam\SourceModInstallPath