Tonight at Gallerie Icosahedron in New York, the much-liked Now Ensemble presents a concert of music by Nico Muhly, Judd Greenstein, Mark Dancigers, and William Brittelle — the last-named presenting the world premiere of his new work Michael Jackson, "a six-minute work written in an effort to juxtapose the brutally crucified public figure with the artistic persona created through the music he performed and (occasionally) wrote."