The youth movement in the music biz was given a tremendous boost [recently] when Janis Ian made her concert bow to a near-capacity audience. Only 16 years old, Miss Ian stunned her peers and her elders with the power of the material…. Miss Ian's celebrated number about an inter-racial love affair, "Society's Child," was only a partial tipoff on the calibre of this girl's compositional talents. She can write blues, rock and folk on any topic, from prostitution, old age homes, masochism, suicide, self-pity to the Vietnam war. As remarkable as the material, even more striking was the absence of precocity or self-consciousness.