The "Whitney Biennial" has always thrived on controversy, and this year's edition is no exception; in fact, the 2000 show has been embroiled in one sort of contretemps or another since its planning stages. From the departure of one director (David Ross) and the appointment of another (Maxwell Anderson) to the departure of the show's original curator (Thelma Golden) and the appointment of curators from outside the institution—a "Biennial" first it has all been very...complicated (almost as complicated as E.V. Day's intricate White Bombshell, pictured). The latest brouhaha involves the inclusion of Sanitation, an installation by the German-born political artist Hans Haacke, which compares Rudy Giuliani's behavior over the Brooklyn Museum's "SENSATION" exhibit last fall to Nazism. Okay, maybe Haacke's exaggerating; you can judge for yourself starting Thursday 23.