I find this interesting as well. It's a rare song that I like /because/ of the lyrics (or even despite the lyrics). For the most part they are just part of the music - another instrument adding complexity to the song.
Despite that, I can't really program while listening to songs with lyrics. Somewhere in my brain a thread is running parsing the lyrics and stealing cycles.
If it helps color in my picture a bit, I go to sleep listening to (spoken) podcasts every night. I can be asleep in minutes even listening to reasonably interesting content. I suspect this will bite me in the ass if I ever decide to go back to university ;-)
Despite that, I can't really program while listening to songs with lyrics. Somewhere in my brain a thread is running parsing the lyrics and stealing cycles.