#10 caught my attention:
The flouride in tap water may taste unpleasant.
Flouride is an iodine blocker (so is chlorine which is added to city water), meaning that it takes the spot in cells where iodine would go. Iodine is very important for thyroid function, so beware water with flouride and/or chlorine. Who knows what the long-term impact will be on your cat's thyroid? Better safe than sorry.