I've also heard that the protein to carbohydrate ratio in chocolate milk is the right number. (I'm not sure what level of milkfat this applies to, or how rigorous the science behind this is though.)

Personally, I love chocolate milk as a recovery drink after a really long run or ride (I don't do it after regular workouts). One of the local dairies here makes a really good organic chocolate milk- I can't imagine that any of those powdered recovery drinks would be anywhere near half as good.