Misty May-Treanor danced on the sand and then off it, leaving Horse Guards Parade with Kerri Walsh Jennings and a third gold medal. Playing in the Summer Games together for the last time, the twice-defending champions extended their unbeaten streak to 21 in a row -- through Athens, Beijing and now London -- by defeating Jennifer Kessy and April Ross 21-16, 21-16 in an all-American final on Wednesday night.