The new interface has focused on cleaning up all visual clutter. It is much easier to scan through lists and know where you are.
Albums are represented by covers in a grid and they make use of the drawer effect used on ios folders to show the album, its songs, and additional information. This helps to keep the user where they for a better flow.
The player has even more options but have been compacted nicely into the small space. One nice addition is the star rating shows instantly in all places its displayed as you are rating it.
The Itunes store sees some much needed improvements, a unique on is being able to sort comments in various ways that would be helpful to someone considering the movie, app, or tv show, etc.
The search bar has also seen an upgrade as it now provides an array of useful information as the user types.