I think the take-away quote from the article is:
"This type of research is valuable to point to potential toxins in the environment -- only further studies will confirm if this is a concern or not," said Dr. Gordon Ewy, chief of cardiology at the University of Arizona College of Medicine in Tucson, Ariz."

One such test, even a large and well designed one, is not the final word. If it makes you feel better to work on avoiding such plastics then your free to do so. If this means fewer people use bottled water it would be a good thing even if this link was shown to be nonexistent.

I would point out that Diabetes was around long before these plastics and certainly normal exposure doesn't automatically mean your afflicted. It may, to some unknown degree, increase your risk but the effect is, at worse, clearly on the margins.