I don't know about you, but I definitely use music to mark periods in my life. The summer I listened to Dashboard Confessional's "The Places You Have Come to Fear the Most" album non-stop will forever live on in summertime-epic-dreaminess/awesomeness (Hey, I was 18, and that's the perfect description for it). The fall when Dixie Chicks' "Not Ready to Make Nice" made an uncountable number of plays on my iPod? Yeah, not so great. So when we look back on the summer of 2011, what will be "the song" that defined it? According to Billboard Magazine, several Channel 957 artists' songs are in the running.