Update: I filed a bug with Apple WRT to inconsistencies in SU and the demise of thePackages folder. Here's what they had to say: "Engineering has provided the following feedback regarding this issue: Look in /Library/Updates. /Library/Receipts contain pkgs but they are not the full packages, only the package receipts (metadata)." So, what I provided earlier in this thread wasn't the total picture and waserroneous. Interestingly enough, the iTunes and QuickTime packages weren't saved to Updates, but remants were put in Receipts; whereas the MacOSXUpd10.5.1.pkg, LoginKeychainUpd.pkg, and RemoteDesktopClient.pkg (3.2.1) were placed in the Updates folder.