My Two iTunes 12 Bugaboos
I don't like to complain, but:
1) When you select a CD in iTunes 12, the keyboard shortcut Command-I no longer shows the CD's Get Info panel. The "Get Info" button does work as expected.
2) Likewise, while a CD is selected, the View menu's "View Options..." and Command-J shortcut do not work. The menu flashes, which is quaint. But you can only show/hide the columns of a CD playlist by right-clicking the column headers.
3) (Did I say two?) Speaking of Showing columns: you can only show/hide one column at a time by using the "Show Columns" popup in the "View Options" panel. Try turning fifteen or so columns off or on and see how you feel afterwards.