The 10.6.4 Update is recommended for all users running Mac OS X Snow Leopard. It includes Safari 5 and general operating system fixes that enhance the stability, compatibility, and security of your Mac, including fixes that:– resolve an issue that causes the keyboard or trackpad to become unresponsive– resolve an issue that may prevent some Adobe Creative Suite 3 applications from opening– address issues copying, renaming, or deleting files on SMB file servers– improve reliability of VPN connections– resolve a playback issue in DVD Player when using Good Quality deinterlacing– resolve an issue editing photos with iPhoto or Aperture in full screen view– improve compatibility with some braille displaysFor detailed information on this update, please visit this website: http://support.apple.com/kb/HT4150.For information on the security content of this update, please visit: http://support.apple.com/kb/HT1222.