The 10.0.1 .pkg
You can intercept the download, so you'll have a
copy of the pkg for looking at. When the actual install is
in progress, open Terminal.app and look in the /tmp
directory. There will be a numbered directory (your user
number in the great Unix scheme of things). Looking in
that directory you should find a package called
10.0.1.pkg. This is the package that contains the
majority of updates to 10.0.
Useful if you'd like your own copy of the updater.