Place the cream cheese, blue cheese, cheddar cheese, mustard, Worcestershire, garlic powder, and salt in a mixer bowl and beat at low speed just until well mixed. Stir in the pecans and currants. Taste and adjust seasoning. Refrigerate the cheese mixture for 30 minutes or until slightly firm, then shape into a ball. Roll in the chopped parsley to coat well. Cover with plastic wrap and refrigerate until ready to serve. Let stand at room temperature for about 30 minutes before serving. Place on a platter surrounded with crackers and apple wedges.