If the labels are accurate and do identify the processor powering Apple’s as-yet unannounced iPhone 4G as being an A4, it would be the first iPhone not to use a third-party processor.
Among the unknowns, of course, is the clock speed of the processor inside the prototype, let alone what Apple might actually ship. The iPad weighs in at 1GHz, one of the fastest, if not the fastest, ARM-based processors on the planet. The iPad is also much faster than the iPhone 3GS, and a 1GHz A4 in the iPhone 4G would likely make it the fastest smartphone on the market, and then some.