I would suggest that these tests are not a good way to work out whether we should be listening to something. Firstly significant part of whether a CD gets sold in Christian stores or a song gets played on Christian radio is not a decision about the theological soundness of the lyrics, rather a business decision as to which grouping of media and sales outlets they will send it to that will get them the most sales and fans. Some Christians who haven't compromised their lyrical standards at all choose to put their music out in the mainstream arena rather than the Christian one because that is where they believe it will make the biggest impact. Secondly, just because the CD is in a Christian bookstore doesn't mean what they are saying is biblically sound. This is the case for Christian books too, it is starting to seem like a lot of the time the more copies a book sells in the Christian market the more likely it is to have serious theological flaws. The Jesus Per Minute test fails because there as a lot of topics for songs that are totally biblical and appropriate for Christians to listen to but don't lend themselves to mentioning Jesus every few lines.
So if that doesn't work, how do we assess the appropriateness of the music we listen to? We tend to think about what we've been listening to, the lyrics get stuck in our heads and they can start to subconsciously impact our beliefs. Because of the impact of music on how we think, Philippians 4:8 is an excellent place to look.
Finally, brothers, whatever is true, whatever is noble, whatever is right, whatever is pure, whatever is lovely, whatever is admirable—if anything is excellent or praiseworthy—think about such things.
Based on that, here's some questions I think we should ask.
Is this song telling the truth?
Is this telling us the truth about God as he is revealed in the bible rather than some of the popular but false images of God that are around? Does the worldview it expresses line up with the bible or is it some other view (eg. Life is all about you/getting stuff/having fun)
Does this song encourage you to view people the right way?
Does this song speak about people in a respectful way or does it portray groups such as women or ethnic minorities in a disrespectful or degrading way?
Does the song encourage noble and praiseworthy behavior?
Is this song glorifying behavior that is inappropriate for Christians such as violence, revenge, hate or greed? Is the activities described in this song even legal? Would acting like what the song encourages make you less or more Christ-like?
Does this song encourage purity?
Does this song go into an inappropriate amount of detail in areas that are likely to cause me temptation to do the wrong thing or dwell on wrong thoughts? Does it encourage sexual activity outside of marriage which is inappropriate for Christians?
How much excellence can be found in this song?
Is this song actually good enough musically and lyrically that it is actually worth listening to repeatedly or is it just mindless rubbish?
Sometimes these criteria will agree with the traditional guidelines. Many times it will not. I've heard stuff that is sold through the Christian industry that never should have been due to inappropriate lyrical content and music from outside the Christian industry that is totally suitable and worthwhile for Christians to listen to and think about. Let's ditch the fights over the labels someone has put on it and instead start choosing our music based on what it actually says.