Ironically, it's songwriter Diane Warren and not Beyoncé herself who defines the diva's fourth album, "4," with a line like, "I want to leave my footprints on the sands of time." Less flashy but just as ambitious as 2008's "I Am . . . Sasha Fierce," the new set finds Beyoncé in genre-blending, career statement mode, weaving together mostly pop and R&B flavors in these dozen tracks. The album is quieter and torchier than its predecessors, with the singer delivering uniformly stellar vocal performances. Rich but not over-sung, she ruminates on love ("1+1"), lost love ("Best Thing I Never Had") and the gray areas in between ("I Care," "I Miss You," "Start Over"). Messy arrangements trip up "Party" (with André 3000 and Kanye West) and the Boyz II Men-sampling "Countdown." But the track "Love on Top" is a buoyant slice of girl-group pop and "Run the World (Girls)" is the expected shout-out to the independent women who may or may not have put a ring on it since Ms. Fierce last reared her head.