However, there is also an ongoing argument over going in/out of songs. The official line where I do shifts is "do NOT talk over songs that end". Simple rule that I've never broken, even before I took the role on. But how do I know how songs end? Some playout systems will tell you, but that's usually unreliable at best.
My approach - PFL is key. I listen to the start and end of the song. I've then got little symbols I put on the show notes to indicate how the song starts / ends. As this may be useful to some other people, here is the key:
Song Outros
Song Starts
In addition to the into time in seconds, I usually mark the first thing I'll say over an intro with an asterisk (*). This is quite useful to prevent me overfilling that intro. Most time, I've only got one or two lines in the intro. It allows me to enjoy the music as well. :)