Security Update 2005-008
There's a new Security Update in the queue if you run Software Update: Security Update 2005-008, which is supposed to include: ImageIO, LibSystem, Mail, QuickDraw, Ruby, SecurityAgent and securityd. More info found here.
A word of warning, though: Security Updates have been . . . problematic in the past for some people, and one of our readers, Sean, writes in with this warning about this update: "Got home today and saw a Security Update in Software Update. Went through it, told me to restart, and I did. When I logged in after the reboot, it asked me for my Keychain password for "System". I entered it, and it told me I was wrong. Tried again, same thing. Tried again, and now I've entered the "wrong" one too many times. I guess this update makes my system so secure that it is unusable :) Might want to warn TUAW users to hold off on the update, if this happens to anyone else."
Thanks, Sean, and good luck!
UPDATE: Well, it worked fine for me and several other users in the comments. Also, there's an iPod updater too.