Now available via Software Update:
The 10.4.2 Update delivers overall improved reliability and compatibility for Mac OS X v10.4 and is recommended for all users. It includes fixes for:
file sharing using AFP and SMB/CIFS network file services
single sign-on authentication and reliable access to Active Directory servers
autologin for managed user accounts
AirPort and wireless access
Core Graphics, Core Audio, Core Image, including updated ATI and NVIDIA graphics drivers
Finder updates including finding on Kind and using Slideshow
synchronizing your iDisk with .Mac
installation reliability
managing Dashboard widgets
Address Book, Automator, iCal, iChat, Mail, Safari, and Stickies applications
compatibility with third party applications and devices
For detailed information on this Update, please visit this website: http://www.info.apple.com/kbnum/n301722
For detailed information on Security Updates, please visit this website: http://www.info.apple.com/kbnum/n61798