So I saw this add on TV, for Gatorade's "Fitness Water". The add pretty much said "It's not about whether you're fit or not, but how fit your water is!"
It really amuses me all these new additives and stuff to water to make it better, more improved and healthier etc. I don't know why people actually get sucked into it.
I think it's all crap, but in saying that - I have no evidence to back me up. I just don't think its worth the extra money or any of the extra bother.