1. Heat oven to 325°F. Stir together graham cracker crumbs, 1/2 cup toffee bits and melted butter. Press onto bottom and 1/2 inch up sides of 9-inch springform pan. Bake 10 minutes. Cool.
2. Increase oven temperature to 350°F. Beat cream cheese, sugar and vanilla until smooth. Gradually beat in eggs, beating just until blended. Fold in milk chocolate chips and 1/2 cup toffee bits. Pour into prepared crust.
3. Bake 45 to 50 minutes or until center is almost set. Remove from oven to wire rack. With knife, loosen cake from sides of pan. Cool completely.
4. Evenly spread whipped topping over surface of cheesecake. Sprinkle remaining 1/3 cup toffee bits over whipped topping. Cover; refrigerate several hours or until chilled. Cover; refrigerate leftover cheesecake. 10 to 12 servings.