I am currently downloading Mac OS X 10.5.1 from Software Update. Weights 39.8 MB for my Intel iMac.
The 10.5.1 Update is recommended for all users running Mac OS X Leopard and includes general operating system fixes that enhance the stability, compatibility and security of your Mac.
iCal alarms are now more reliably delivered via email.
Hoping for a fix for the wireless to airport extreme problem. Any airport updates in the 10.5.1 update?
AirPort
Allows password-protected accounts on AirPort Disks to show up on in the Finder's Shared Sidebar.
Resolves an issue with saved passwords for wireless networks.