Ever since Mac OS 10.8 Mountain Lion, Notification Center has been ported over from iOS to live in the screens of our Mac computers.
It used to be that Notification Center displays alerts of things we commonly would like to be notified about, e.g. calendar events and Facebook or Twitter updates but new versions of iTunes now include a radio track banner notification whenever iTunes changes tracks.
Whilst this feature may be loved by some (you can skip songs by clicking the “Skip” button in the radio track banner that appears), there is respite for those who prefer not to be annoyed by trivial notices.
The iTunes track notification can be switched off from inside the iTunes Preferences General Tab: