Butter two 8x4x2- or 9x5x3-inch loaf pans. Place nuts in bottom of prepared pans; set aside. Stir together flour, baking powder, cinnamon, 3/4 teaspoon nutmeg, soda, and salt. Set aside.
In a very large mixing bowl beat butter with an electric mixer on medium speed for 30 seconds. Add granulated and brown sugars and vanilla; beat 1 to 2 minutes or until well combined. Add eggs, 1 at a time, beating just until combined after each. (Mixture may look curdled.) Beat in pumpkin. Add flour mixture and milk alternately, beating on low speed until well blended after each addition; scrape sides of bowl.
Pour batter into prepared pans and smooth tops with a rubber spatula. Bake in a 350 degree F oven about 1 hour or until a wooden toothpick inserted near center comes out clean. Cool loaves in pans on wire rack for 15 minutes. Loosen edges with a narrow metal spatula and remove from pans. Cool completely on wire racks, nut side up. Store in an airtight container in a cool place up to 2 days.
To serve, place cakes, nut side up, on a serving plate. Brush tops with 2 tablespoons of the maple-flavored syrup. In a chilled bowl beat whipping cream, remaining 2 tablespoons syrup, and 1/2 teaspoon nutmeg just until stiff peaks form. Serve the cream in a bowl with the cake. Makes 2 loaves (16 to 20 servings).