Circa 1995, I went through her greatest hits album in its entirety. The process only entailed 6 hours of my time. The immediate tangible benefit was that I was able to hold my own during KTV meetings. A secondary, and more important, benefit was that I learned how speak Chinese like a non-peasant.
I formally studied Chinese at the one of America's top universities, and I won't dispute the fact that the 5000 characters imparted upon me there haven't helped me, but simply listening to music got me one third of the way.