Iced tea, coffee, milk, and water are served with your meal for free. Soda and everything else costs you. We are iced tea drinkers but I also get water with lemon as it cleans the palet so that you can savor the differant tastes of the dishes.
When I called Carnival last week this is what I was told. Iced Tea, Water, Coffee, Lemonade, Fruit Punch (and juice at breakfast) are included in fare. Kids 12 and under get free soda in the dining room only.
Just returned from the Celebration on 4-17. Everyone assigned to our dining table brought their coke/pepsi with them, and just asked for ice. It wasn't a problem, no one stared in disbelief or anything! Actually, I think others wished they had done the same.