Chuck D and Flavor Flav, once no less than lyrical revolutionaries, are now best known as a radio host and reality TV embarrassment, respectively. And with guest spots from MC Ren, Sister Souljah and Floridians Dead Prez, Rebirth takes on the feel of a reality show of its own: former polemic rappers reunited. The tracks are unified by run-of-the-mill production from fellow radical Paris (on whose label the disc is released) and the typically fuming eloquence of Chuck D. Surprises drop on songs like "Plastic Nation," an aghast reaction to the nip/tuck obsessions of young women, and "Coinsequences," full of naive rationalizations for Flav's VH1 show The Flavor of Love. The remainder plays like a greatest B-sides PE collection. Rebirth, for all its sound and fury, is not a catalyst for change; rap just doesn't serve that purpose any longer. However, there's still no more reliable source of agit-hop.