Colbie Caillat w/ Howie Day and Trevor Hall

The daughter of Fleetwood Mac producer Ken Caillat, clean-scrubbed adult alternative it-girl Colbie Caillat offers a fluffy alternative for “Grey’s Anatomy” viewers who find Norah Jones too heavy and Jason Mraz too dark. Caillat’s latest serving of Splenda-sweetened, decaf coffeehouse pop is this year’s Breakthrough, which she brewed with an army of producers and songwriters, including “American Idol” judge Kara DioGuardi. Caillat shares tonight’s bill with sensitive songwriter types Howie Day and Trevor Hall.