Appleis update notes:
The 10.4.5 Update is recommended for all users and includes general operating system fixes, as well as specific fixes for the following applications and technologies:
- iChat video conferencing
- Safari rendering of web pages
- usability of Dashboard and widgets
- viewing of QuickTime streaming media behind a firewall
- printing to some Epson printer models
- iDisk and Portable Home Directory syncing
- time zone and daylight savings for 2006 and 2007
- VPN connections to Cisco servers when using NAT
- compatibility with third party applications and devices
- previous standalone security updates
You can find more detailed information on the above update elements at the Knowledge Base article for the update. The update can be downloaded through Software Update, and the file is 6.4MB.