We started this on January 4th, 2006....then we ended it on Valentines day....a few of us kept going, but then I, myself, died down. Just recently (maybe a week or so) have started back up again. So this last time, I would say I've been doing it about a week - week and a half now.
Oh and I remember I cut way down on my caffiene (coffee) and cut to one cup of coffee a day. Switched to green tea....I think this helped alot too. But never counted any other beverage as my 8 glasses of water. So my 8 glasses of water were above and beyond any other beverages I consumed.