How can I fix the iTunes 11 mini player that won't show the track name?
The answer is in the comments on this TUAW post. The keyboard focus on the mini player (indicated by the blue focus ring) is on one of the playback controls, which prevents them from hiding. Click the mini player background to bring it to the foreground, then press tab until the focus ring moves to the Up Next or Search icons, and track information will appear whenever the mouse is not over it.