I spent a long time in the upper echelon of the music business, starting as a vocal coach/audio engineer and they working up into studio management and talent development, so I love to watch Idol to see if I can guess from the raw auditions who will do what. I kind of watch it from a different perspective than most others.
When they show picks a theme, like "Country Night", the artist is to select a song from that niche and THEN deliver it as if it would be the way that artist would record it for his or her own album. You would not expect many of the contestants from this year to perform a song in a country style, as that is not the style of music they choose.
A good song is a good song, and can translate into any style, it's just that YOU, the audience, will usually prefer to hear the song in a style of music you like and/or, with a cover song, the way you've most enjoyed it in the past. So, that's why it's a difficult between singing like a "karaoke singer" and making it your own and still be accepted by the audience.
The difference between a "cruise ship singer" and an "American Idol" is charisma. Two people can have exception vocals, but if one doesn't have star quality, they can forget a future. I think that is the problem with Matt, Lil, Anoop, Chris...can't remember who else is left...Danny, Allison and Adam have that "extra something" that would give them the impetus to be successful artists, if they are matched with the correct material and producer.
Adam does some amazingly difficult stuff when he sings. His singing ability just devastates the rest of the crowd. He might not be your choice of style, but he has chops. He's been my choice all along, if I had one I could sign.
Personally, I do NOT like the new judge. She is the one I'd like to send home next. LOL.