Rumors of the next iPhone have been swirling ever since the device was a no-show at WWDC earlier this year, but now we have the first rumored date of Apple's next media event: September 7.

Japanese site Kodawarisan (via MacRumors) claims that Apple will hold their traditional fall media event on this date which has typically been reserved to introduce new iPods. We haven't heard much of anything about new iPods at this point and previous rumors of a September or October iPhone launch align perfectly with this date.

Apple broke tradition in June when the annual conference passed without a peep about the next-generation hardware. WWDC had been the launching pad for the past three iPhones. The iPhone 3G was introduced on June 9, 2008. The iPhone 3GS was announced on June 8, 2009 and arrived on June 19, 2009 in the first countries. The iPhone 4 was announced on June 7, 2010 and released on June 24, 2010.

There has been a lot of speculation as to why we haven't seen a new model in over a year. The most popular guess is that Apple experienced some overheating issues with the dual-core A5 chip that is said to power the iPhone 5. There could be some validity to this claim, especially if the rumor of a thinner and lighter iPhone is to be believed. Other gossip suggests the staggered announcement is a strategic move used to buy time for 4G LTE development and integration or to counter Google's planned Ice Cream Sandwich release.

Details on the next-gen iPhone are bleak at this point but the prevalent rumors point to faster internal hardware, a thinner chassis and possibly a larger "edge-to-edge" display. Still others believe that the next iPhone will feature a radical new design with a contured rear panel.