Q. I installed 10.1.0 and SoftwareUpdate shows no updates!

A. This is due to a security update released in July, 2002, which changed the way SoftwareUpdate looks for updates. You need to go to Apple Knowledge Base 120136: Security Update 7-18-02 for v 10.1: Information and Download and manually install the security update before you can use SoftwareUpdate.

Q. How can I prevent normal users from running SoftwareUpdate?

A. You can change the permissions on the SoftwareUpdate application so that only administrators can run it.

[localhost:~] you$ sudo chmod o-x /System/Library/CoreServices/Software Update.app 

When normal users log in, it will try to run SoftwareUpdate but fail silently (with no error message). If the normal user goes to the SoftwareUpdate pane in SystemPreferences and tries to run it manually, it will spin for a second, then give them an error message.