One of the more useful ones is a small shell wrapper around homebrew cask that batches installation packages based on category, and one that automates symbolically linking dotfiles using a configuration file.
Which leads me to my second point: How would you go finding all those still relevant dotfiles and folders for settings of programs you still want to use and, with wiping, removing all obsolete ones?
A much more comprehensive collection of tweaks and tips for OSX administration.. though I did learn a few things from WhiskyKilo which were quite interesting - I have wondered how to do this from the command line for years and am glad to have finally learned: "sudo softwareupdate -i -a" .. fantastic!
I'm assuming that it won't install App Store software that is in your account but not installed on the current machine? Which if so is a shame that Apple haven't exposed this via the command line (preferably specifying the name of the application to install).
Edit: I'm an idiot. I thought the title referred to a VCS repository.
What do you use instead of itunes?
