Fire up Software Update, Mac users. Security Update 2008-002 has been released. According to Apple, this update "...is recommended for all users and improves the security of Mac OS X. Previous security updates have been incorporated into this security update."
So, it improves security. How exciting. As usual, we ask you to report any problems you encounter after installing this update. Good luck, true believers! Note that this update, like the earlier Safari 3.1, requires a reboot.
Thanks to everyone who sent this in!