Mostly agree with SSP. And especially with "cocktail" juices, which are often only 10% juice and loaded with high fructose corn syrup. I only use juice for 2 things: a splash in my recovery drink if I don't have any convenient fruit to throw in the blender; and since I use water on my cereal instead of milk, sometimes it will need a splash of juice (again, if I'm low on convenient fruit).
I also find that if I am craving something with a little flavor to drink, that just adding a little juice to my water (about 4:1 water:juice) does the trick. I found that my tastes adjusted to this almost immediately -- that is, full strength juice is now tastes way too strong to me.
(Edit: I'm not saying juice is bad, at all. This is just in reference to reducing empty calories and sugar intake.)