Be careful of how much fruit juice you drink. It has a lot of calories in it. A serving size (USDA Food Pyramid) is only a 1/2cup.
Fruit juice is concentrated and powerful. An 8 oz. glass of apple juice may contain about 10 apples-worth of juice. 8 ounces of orange juice could be the equivalent of 6 oranges. You wouldn't eat that many in one sitting, would you?
Many fruit juices are loaded with sugar, too, especially naturally bitter juices like cranberry or grapefruit. Those need added sugar to be palatable. Beware of any juice labeled "drink" (they contain hardly any real juice at all), or "cocktail" (that means it's full of sugar).
While it's better to actually eat the real fruit, some fruit juice is OK, and good for you. Certainly better than soda.