With the exception of those $5 to $10 cold-pressed juice bottles, virtually all juices sold in the United States - both the refrigerated and shelf-stable versions - have been pasteurized. This heat destroys some of the antioxidant content of the fruit, especially its vitamin C. In fact, the only reason orange juice has any is because they add it back in (the chemical version, ascorbic acid) after the pasteurization process takes place. In the case of blueberry juice, its ORAC value is about half that of fresh blueberries. Regardless, there is still a respectable amount of antioxidants in blueberry juice. For comparison purposes, on an equal weight basis, it still contains more than kale.
ORAC Source
USDA Database for the Oxygen Radical Absorbance Capacity (ORAC) of Selected Foods, Release 2 - Prepared by Nutrient Data Laboratory, Beltsville Human Nutrition Research Center (BHNRC), Agricultural Research Service (ARS), U.S. Department of Agriculture (USDA) - May 2010