MIX crumbs and butter. Reserve 1/4 cup of the crumb mixture; press remaining mixture onto bottom and up side of 9-inch pie plate. Refrigerate until ready to fill.
BEAT pumpkin and marshmallow creme in large bowl with electric mixer or wire whisk until well blended. Gently stir in 2 cups of the whipped topping; pour into crust. Sprinkle with reserved crumb mixture; cover.
FREEZE 4 hours or until firm. Remove from freezer. Top with remaining whipped topping and pecans. Place in refrigerator 30 minutes before serving to soften slightly. Store leftover pie in freezer.