Got a 12-pack of Happy Water delivered today, from the back of an unheated truck, cold on arrival. Me and 6 office mates gave it a try. Everyone liked it. The packaging is sleek, professional, and yellow (happy). Not sure if this is a placebo effect but I actually felt a bit "smiley" while drinking. Couple other people got a bit goofy, too.
The water business is complex and crowded, and Happy Water probably doesn't have a chance to gain any significant traction. But after trying it, I think it's chances have doubled from "none" to "slim". It really is a worthwhile try.