We once hired Buffalo Springfield for a college party. There was only around 60 people in the crowd. They sounded FANTASTIC live, and I bought their album.
I don't listen much to the album since it doesn't jive with what I heard them play.
A couple of things pop up in previous posts concerning contemporary sound:
Bass - in a lot of music there is no bass, a la White Stripes. (I have received comments like "Nice to hear bass again" while testing songs on Jango.)
Repetition - Contemporary Songs rely on repeating a phrase, repeating a phrase, repeating a phrase, repeating a phrase, repeating a phrase, repeating a phrase....

Counterpoint - there are very few contrapuntal lines. Even in songs with bass, the bass follows the lead guitar.
As an aside, the Author of FutureHits DNA states that intros should be less than seven seconds. He stated on the Taxi TV show that he rather likes Mumford & Sons. I timed their intros at up to 50 seconds. Just goes to show that no one knows what they are talking about.