There's no question about P!nk's commitment to pop dominance, but her relationship with it is full of experimentation. Her stylistic breadth spans the punky bounce of “Trouble,” the brutally honest R&B balladry of “Family Portrait,” and the biting dance-pop of “Stupid Girls”; she's also harmonized through a woozy romance with country star Kenny Chesney and belted alongside acousti-pop heroines Indigo Girls.