Why? That's not entirely clear. Perhaps the release date was too much of a moving target to risk booking a large space like Yerba Buena Center for the Arts (YBCA), which has hosted a number of big product unveils in the past. Perhaps, the company felt a more intimate venue was best for newly installed CEO Tim Cook's first media event. Perhaps YBCA was simply already booked. Whatever the reason, the world will get it's first look at the next iPhone at Apple's Town Hall Auditorium in early October.
Following the October 4th Event, Apple is expected to release iOS 5 on October 10th and the launch the new iPhone on October 14th.