From Rap's Rhythms, a Retooling of Poetry
Spoken-word movement is retooling the use of the rhymes and rhythms that are the foundation of rap music, discarding its violent imagery, drugs, misogyny and recording-studio gimmickry and keeping the music that may accompany it in the background; movement has been evolving in clubs, cafes and workshops for several years, well before the soul-searching prompted by the slaying of Tupac Shakur; poets examine issues of passion, pain and poverty, and their heroes are less likely to be Shakur and Snoop Doggy Dogg than literary figures like Langston Hughes, Amiri Baraka, Nikki Giovanni, Gil Scott-Heron and the Last Poets, the village elders of rap; photos (M)