The latest in iPhone 5 rumors claims that Apple won't be starting mass production of the iPhone 5 until September, which corroborates previous reports that Apple won't be unveiling the device at WWDC this summer.
If production doesn't start until September, Apple could be waiting to unveil and announce ship dates for the next gen iPhone at their annual September event. Although iOS 5 will be previewed this summer, there could be an official launch of Apple's new software alongside an iPhone 5 announcement later this year...