In tribute to the famous "Hello Dolly" plugin by Matt Mullenweg comes this new plugin. And how could someone possible name a new default plugin other than "Hello World", as it's THE definition for a default exmaple :)
I could not change the lyrics file on the plugin settings page. I found that if I removed the call to wp_unslash() it worked fine. I was happy until the last update undid it, so I figured I'd let you know what I experienced.
UPDATE: Now I feel silly. While it did not work on my dev machine (XAMPP) it works fine on final production server.