If you don't have an ssd, updating apps will almost freeze your system. But Steam has also had this issue when updating your games. Since I have an ssd all these issues are goneiTunes on Windows runs as if it uses the most heavy resources possible, while any other program doesn't have as much issues. It's just plain slow. Apple could refine it more I'm sure, but I doubt they care.
Nothing wrong with it but its just a better experience on OS X.