I’ll admit that I didn’t know who American Authors was when it played the RadioBDC Live in the Square block party in October. And to its credit, now the group of Berklee dropouts is everywhere, riding its radio-friendly lite rock single “Best Day of My Life” straight into the hearts of music fans impatiently awaiting the next Train album. The band scored the designation of VH1’s featured “You Oughta Know” artist for February. So what’s the next step? Oh yes, “Ellen” and her dance-crazed audience. Watch the Brooklyn-based band light these ladies on fire on today’s show.