I'm pro.  Cracking does improve digestibility and feed efficiency, but I don't believe it is enough to pay for the cost of the cracking plus the shrink from cracking.  Whole corn reduces the risk of acidosis because it is less soluble.  Whole corn has an effective fiber component which reduces the hay or other roughage needed in the diet.  Ohio State has research that shows improved performance on calves when fed whole corn versus processed corn - theory being the long fed calf gets some rumen damage from the cracked corn over time.  Whole corn makes bunk management very important, so that the rate of passage is not too fast.  If the rate of passage is controlled, very little corn passes through.  Because of this, cracked corn is better in higher roughage diets like a backgrounding diet.