In A Large Bowl, Beat The Cream Cheese, Butter And Vanilla Until Fluffy. Gradually Add Sugars; Beat Just Until Combined. Stir In Chocolate Chips. Cover And Refrigerate For 2 Hours. Place Cream Cheese Mixture On A Large Piece Of Plastic Wrap; Shape Into A Ball. Refrigerate For At Least 1 Hour. Just Before Serving, Roll Cheese Ball In Pecans. Serve With Graham Crackers.