Pop vs. Coke

Found this off my friend Jeremy's blog. What do you call your fountain drinks? I have always gone with Soda (I don't really know why). Living in the south though I hear about Coke all the time (even if people want a Dr. Pepper they call it coke). And I always found it funny to hear "them crazy yankees" call it Pop. Come on now, Pop?!?!
So what do you call it? Here is a map of the breakdown of the U.S.