I've always read complaints about the taste of the water at WDW, but personally, I just don't get it. Tastes like water to me!
Maybe it's because up until 8 years ago I've lived my entire life in big cities AND always drank tap water.
I buy bottled water at home only for convenience, such as taking some in the car. One of my poker buddies recently went into my fridge and looked at the water bottle label; the water was "made" by Nestle. He asked me, "Does Nestle make good water?" I looked at him like he was from Mars, because I swear I couldn't tell you one bottled water from another from tap water.