Jackie Greene has undergone quite a transformation since he released a pair of albums on Verve Forecast in the middle of the past decade. Back then he was everything you’d expect from a troubadour with acoustic guitar in hand and harmonica holder around his neck — you know, someone taking aim at weathered and weighty expression. Thing is, he’s since gone where descendents of Dylan don’t usually go: into a steady stream of collaborations with giants of folk- and blues-rock jamming like Phil Lesh and Gov’t Mule. And, interestingly, Greene’s most recent album, 2010’s Till the Light Comes, staked out territory between roots rock and power pop. It was hooky as hell, and a good reason to be on the lookout for his next musical move.