The Bottled Water Challenge
An Alternet article sums up this debate well and highlights a taste test the author compared to the Pepsi challenge. Most of the tasters couldn't tell the difference between Boston's tap water and their bottled favorites. The motivation behind the taste tests, given by Corporate Accountability International (CAI), is to try and deter the "increasing commodification of a resource that should be a basic human right, not a product on sale for $1.50 at the local convenience store."
In the U.S. tap water is strictly regulated by the EPA, while the FDA monitors much of the bottled variety. However, "A 1999 study by the National Resources Defense Council of more than 1,000 bottles of water found that, while most bottled water was safe, some brands violated strict state standards on bacterial contamination, while others were found to contain harmful chemicals such as arsenic. The report concluded that bottled water was no safer than water taken from the tap."
Of course there are other issues such as the draining of acquifers in some areas, (at times unsuccessful) water privatization of municpal systems, and the costs and conveniences of the bottled stuff. Outside of the U.S., especially in mid and lower income countries, people are forced with tougher circumstances than just preference over which safe drinking water to choose. At the very least the CAI taste testing will hopefully get a few Americans to have a greater appreciation for a resource they often take for granted.