http://www.sciencemag.org/cgi/content/full/311/5757/23
[Martin Blume, editor-in-chief of the American Physical Society and its nine physics journals, says that peer review overlooks honest errors as well as deliberate fraud. "Peer review doesn't necessarily say that a paper is right," he notes. "It says it's worth publishing."]
Peer reviews are not infallible, and don't necessarily prove that something is "true".
But I am sure the distinction is lost on you.