In a small mixing bowl, briskly combine vanilla yogurt and raisins until yogurt becomes looser texture. Reserve. For the pancakes, combine flour, sugar, baking powder and cinnamon in a large mixing bowl. In a medium mixing bowl, combine milk, butter, egg, pumpkin and yogurt, mixing well. Add wet ingredients to flour mixture and stir until just moist. Do not overmix. Batter may be lumpy. For thinner batter, add milk. Lightly coat a griddle or skillet with cooking spray and heat on medium. Using a quarter-cup measure, pour batter onto hot griddle. Cook until bubbles begin to burst, then flip pancakes and cook until golden. Serve warm, topped with yogurt-raisin mixture and dusting of cinnamon.