Glatt
Kosher?
That's the real question.
Glatt refers only to meat products.
Coca-Cola is certified kosher for everyday use. But Coca-Cola also make a special "Kosher for Passover" product that is much more popular and better tasting than its regular product, because they use cane sugar instead of cheap corn syrup.
Personally, I stopped drinking sweetened soft drinks several years ago. I prefer plain water, club soda, and flavored club soda. I hate to admit this, but Perrier sparkling water is the best. And as much as I hate to admit this even more, Perrier is much cheaper than any American soft drink when I go across the border and buy it in Canada.