Security Update 2011-004 (Leopard/Leopard Server)
While Mac OS X 10.6.8 resolves numerous security vulnerabilities for Snow Leopard users, those still using Mac OS X 10.5 Leopard should download and install Security Update 2011-004. The most important fix is to AirPort, and it prevents an attacker on the same Wi-Fi network from causing your Mac to reboot. Other affected aspects of Mac OS X include ColorSync, CoreGraphics, ImageIO, MySQL, patch, Samba, servermgrd, and Subversion. Separate standalone updates are available for Leopard and Leopard Server, though it’s still easiest to let Software Update do its thing. (Free; 256.4 MB, 499.8
MB)
10.6.8 update broke many PS printers - search for paused_printers on the Apple discussion boards or see:
https://discussions.apple.com/message/8564035#8564035
I expect to see a quick revision of that update from Apple or a plethora or printer driver updates.