According to several posts on the hackint0sh forum, the chipset that will support the 3G iPhone will be the PMB8878 or better known as the S-GOLD3H.
The current version of the iPhone is powered by the S-GOLD2 chipset, so we might have found the chip that will power the next iPhone.
But maybe apple is planning to use another chipset, we will not know this until final release !
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