TOD:
I don't recall having a particular favorite soda as a kid. My parents only bought it when we went camping or I would have it when we went out to the pizza parlor. Pepsi, Coke, Dr Pepper, Orange Crush, the various Shasta flavors, whatever was around, I drank it. At home all we usually had was Kool-Aid.
As a teen I developed a preference for Pepsi and it is still my favorite. Next to Pepsi, Dr. Pepper is my favorite, although I can count on one hand the times I have actually had a soda of any type in the last 10 years. My beverage of choice now is usually water, decaf coffee, or tea.