Just like STM, you should spend a number of years studying the writings of the Pontiffs on the topic.
Not the Weaklands, Bugninis, nor Pilarczyks.
In other words, seek the truth, not the "tongues which tickle your ears."
That's a word to the wise, if you can handle it.
There are many ways to express our love of the Lord, not just a single one that is acceptable. Pope Benedict has suggested a return to a more sacred canon for music in Mass, mainly because most of the music nowadays is just banal. From what I've read, he's not considering banning any particular type of music, he just wants those leading the music to be sure that it is doing what it should, leading us to a more complete relationship with the Lord, not just be there to entertain the crowd at Mass.