Apple released Mac OS X 10.5.5 update this afternoon. According to information accompanying the update:
The 10.5.5 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.
For detailed information on this update, please visit this website:http://support.apple.com/kb/HT2405.
For detailed information on security updates, please visit this website: http://support.apple.com/kb/HT1222.
The update measured in at 321 Mb for my particular machine and of course requires a reboot. It’s available through “Software Update.”