MacOS – Seeing details on software updates for Mavericks

It appears that some updates have others as prerequisites, and will not show up as available until the others are installed. Thus, Software Update makes a list of all eligible updates, then runs. If a subsequent update was also pending that was not eligible to be downloaded because its prerequisite has not not yet been installed, that update would not make the list. The subsequent check, however, would see if any new updates had been unlocked by the updates installed.

If you are running a software update service on OS X Server, you can see when Apple released each update (and also when the server actually downloaded the file). This is also nice as then you can then only mark an update as viable to your machines once you have had a chance to review things.

Also, for a more lightweight solution, you can look at the downloads web site to determine when a particular package was released.