If you can drink coffee without calories added, I wouldn't necessarily stop, but that's just me. :) You will lose weight with coffee because it doesn't have any calories.
I drink iced tea with Splenda, diet soda, and tap water and Smart Water. Also Crystal Light, which seems to keep me full better than the other drinks.
But I'm not a purist. :( I doubt I could stick with just water, I need the flavors probably for psychological purposes! :D