The always smiley Coco Rocha served as Zac Posen's date at the New Yorkers For Children Spring dinner dance last night. What a fun duo! Coco naturally wore one of Posen's creations, specifically a black and white geometric gown from the Spring '09 collection. Depending on who wears it, it can either be a highly theatrical dress or a lighthearted one. The final say is in your hands, so what do you think — yay or nay?