First off, this is an amazing application with a lot of usefulness. I like the new font, icon, and other interface changes a lot. There are a few things you could add to make it more user-accessible:

1) Make the window adjustable in the bottom right-hand corner so the user can see the full names of songs, albums, artists etc. if they are too big, but still keeping all of the buttons, words, and lists on the left (not centered) while you make the windown bigger.
2) The buttons could also be cleaned up a bit, this seems to be a problem with every version now.
3) In "About" and "Hide" in the menu options, put "iTuner" in place of "Application".