Includes general operating system fixes, as well as specific fixes or compatibility updates for the following applications and technologies:
– RAW camera support
– Handling of large or malformed images that could cause crashes
– Image capture performance
– Mouse scrolling and keyboard shortcuts
– Font handling
– Playback quality, and bookmarks in DVD Player
– USB video conferencing cameras for use with iChat
– Bluetooth devices
– Browsing AFP servers
– Apple USB Modem
– Windows-created digital certificates
– Open and Print dialogs in applications that use Rosetta on Intel-based Macs
– Time zone and daylight saving for 2006 and 2007
– Security updates

Check details here: Tiger 10.4.9