All,
Here is a interesting article from Marketwatch.com about how misleading food labels can be. It turns out that according to FDA rules, companies can legally err by up to 20% on their food packaging labels. That means they can get away with underestimate calories, sugar, trans-fats, saturated fat etc. by up to 20%, and overestimate vitamins and minerals by up to 20% as well.
All the more reason to eat foods without labels, and not to put too much stock in calorie estimates for foods.
--Dean