I looooooove water, but I'm very picky about the taste. Brita-filtered water, for example, tastes greasy to me. Evian seems to quench the best, though Naya (orPoland Spring in the States) is a more affordable alternative. I once found a fantastic Water-pik filter that attached to the faucet, but they discontinued the replacement filters. While I had it, though, it was heaven.
Tap water? Not a chance, at least not in Toronto.
I have a thing for Lipton Diet Peach Iced Tea; I can't get the mix here, so I have to rely on friends in the States. Tastes great, but definitely doesn't quench my thirst like plain water.
I am devoted to my Diet Pepsi (my dad always was mock-angry with me because he had stock in Coca-Cola), but I have to drink 3 or 4 litres a day of water (at least). When I'm cycling, I drink up to 10 litres a day.
And y'know what? I love it.
I especially love my Camelbak, a backpack with a reservoir for water and flexible tubing with a mouthpiece. Mine holds three litres; on especially hot nights - this might be TMI here - I just fill it up with water and ice and keep it by the bed.
As for losing weight... um, I'm not the poster child for that argument, but water definitely makes my skin look better. (I drink diet drinks because I can't stand the syrupy taste of full-cal ones.)