A radio rip of the track made the rounds yesterday, but now we get to hear "Backseat Freestyle," the absolutely vengeful new Kendrick Lamar track, unbleeped and decent-sounding. This isn't a case of Kendrick actually freestyling in the back of a car, going all Black Cab Sessions on us. Instead, it's Kendrick in a vicious-snarl mode that we haven't heard ...