If you're a fan of streusel topping, you'll love this pie. You can substitute Bing cherries and add 1 tablespoon for fresh lemon juice to the filling.
Roll out pie crust disk on floured surface to 13 ½-inch round. Transfer to 9-inch glass pie dish. Trim overhang to 1-inch. Fold edges under. Crimp; forming high rim (about ½ inch above sides of dish). Chill at least 30 minutes and up to 1 day.
For streusel: Mix first 5 ingredients in bowl. Add melted butter and vanilla; rum in with fingertips until small clumps form. (Can be made 4 hours ahead. Cover; let stand at room temperature).
Position rack in center of oven; preheat to 375F. Place foil-lined baking sheet in bottom oven to catch spills. Mix first 4 ingredients in large bowl. Add cherries; toss to coat. Let cherries stand until cherries begin to release juice, stirring occasionally, about 10 minutes. Transfer filling to chilled crust, mounding in center. Sprinkle streusel over, covering completely and pressing to adhere.
Bake pie 20 minutes. Tent loosely with foil. Bake until filling bubbles thickly and streusel is golden, about 1 hour 10 minutes longer. Cool on rack.