Place a greased 9-in springform pan on a double thickness of heavy-duty foil (about 18-in square). Securely wrap foil around pan; set aside.
In a small bowl, combine cookie crumbs and pecans; stir in butter. Press onto the bottom and 1 inch up the sides of prepared pan. Bake at 325 degrees for 9-11 minutes or until set. Cool on wire rack.
Meanwhile, in a large mixing bowl, beat cream cheese and 1/2 cup sugar until smooth. Beat in vanilla. Add eggs; beat on low speed just until combined.
Place 1 cup filling in a small bowl, set aside; stir the pumpkin, cinnamon, nutmeg and remaining sugar into the larger mixing bowl. Remove 3/4 cup of this pumpkin filling and set aside. Pour remaining pumpkin filling into the crust; top with plain filling from the small bowl that was set aside in the beginning. Drop reserved pumpkin filling by spoonfuls over top and cut through filling with a knife to swirl.
Place pan in a large baking pan; add 1 inch of hot water to larger pan. Bake for 50-60 minutes or until center is just set and top appears dull. Remove springform pan from the water bath. Cool on wire rack for 10 minutes. Carefully run a knife around the edge of the pan to loosen; cool 1 hour longer. Refrigerate overnight. Remove sides of pan. Garnish if desired.