-Scrolling seems very laggy when scrolling with the mouse wheel, although dragging with the scrollbar seems fine. This only seems to be happening in the Popular (Now), view. This is under 10.9.
-When I favorite songs, they don't show up in the favorite section although they did after relaunching the app.
-It would be nice if when you moused over a song in the list if it scrolled the full song name into view - at the moment they get cut off and you can't see the full name.
-The song list scrollbar on the right is obscured by the controller at the bottom. I like what you've done with having the songs scroll underneath the slightly transparent controller but the scrollbar should really end where the controller starts.
-I don't seem to be getting notifications from the app even though it's listed in the Notifications app list under the Notifications section of System Preferences.