Mainstream country music has always been popular, but last year it got idiosyncratic, with songs that quoted OutKast, video cameos from Kid Rock, and a rapping black cowboy. This was mostly thanks to the MuzikMafia, a tight collective of Nashville insurgents -- Big Kenny, John Rich, Gretchen Wilson, and assorted friends -- who became part of the Music Row machinery by breaking its protocols.

Hip-hop is such a global juggernaut that it's easy to forget there are still regional black sounds, too. Detroit has its techno and, more recently, its ghetto tech. Chicago has catered to househeads and steppers for decades. Miami's bass music still thrives in obscurity, as did Atlanta's for many years before crunk; and Washington, D.C. go-go remains content not to cross the Maryland line.

"If you talkin' 'bout classics, do my name get brought up?" This is Kanye West on "Diamonds From Sierra Leone," the single that preceded the release of his second album, inquiring after -- or pleading for -- the adulation he so nakedly craves.

Having good taste is easy; translating it into great art is another thing altogether. DJ/rupture and Diplo have both made their names as curators of different strains of the beat diaspora. Rupture links Middle Eastern dub to Jamaican dancehall; Diplo, of the raucous DJ duo Hollertronix, digs Baltimore club music and Brazilian baile funk. And when it comes to hip-hop, they both like it grimy.