The blog-ballyhooed Passion Pit plays a gentle kind of electro-pop that chooses to lilt and sway rather than bump and grind. Chunk of Change, the Boston group's debut EP, is full of flitting falsettos, chirping synths and skittering beats sure to perk up the ears of any Postal Service fan. The good vibes are even on display in song titles: "Smile Upon Me," "Better Things," and the king of the twee heap, "Cuddle Fuddle." The centerpiece here, however, is the sweeping, sample-heavy "Sleepyhead" — the raucous, shout-it-out stomper that feels like a true release after the scampering-about of the first five tracks.