Celebrities Wearing Jason Wu

Wu didn't know the first lady was going to use his design -- although he did create it especially for her, submitting sketches and the final gown to the White House -- making it quite a surprise when she walked out Monday evening. "Mrs. Obama likes to keep her secrets. She surprised me again. She's really good at it," Wu told Women's Wear Daily after she took the stage. (Jacquelyn Martin/AP Photo)