I could definitely drink more water throughout the work day. I tend to sip on my coffee for about 2-3 hours (insulated mug, it stays quite warm) and by the time I hit lunch I realize I could probably use a gatoraide or something. In the evening I'll often pound a few glasses or water or crystal light before I go to sleep. I easily have eight glasses of fluid in a day, but not necessarily water (plus I don't like sipping water I like to throw it back).
I honestly don't know. I think I drink less because, while surfing the web and playing games, I completely forget to drink. Plus it requires walking downstairs, which I usually can't be bothered to do.