Everyone's waiting for the iPhone 5. Phone trade-ins have increased, and even iPhone 4S sales have slowed down as many are holding off until Apple's next iteration of their popular smartphone hits the stores in late September/October. But despite not even being officially announced by Apple, just how popular is the iPhone 5? Based on comments from the senior vice president of worldwide marketing at Apple, Phil Schiller, market research blogAsymco has stated that the iPhone 5 will sell 263 million units in its lifetime.

Asymco's Horace Dediu based his analysis on a statement by Schiller during a testimony at the current Apple v. Samsung trial on August 3.

"Each new generation sold approximately equal to all previous generations combined."

Dediu then splits up iPhone sales by ratios according this statement and concludes that if Schiller was correct, then total iPhone 5 sales would probably surpass 250 million.

But, Dediu himself is not convinced. He predicts that approximately 200 million iPhones will be sold over the course of the next 12 months given a 60 percent growth rate. He then uses the previous set of ratios he had estimated, and states that 85 percent of those will be iPhone 5s, resulting in a total of 170 million iPhone 5s sold through mid-2013.

Given enough time, Dediu does believe the iPhone 5 can surpass 200 million units sold, but hitting the 250 million benchmark set by Schiller might be a little harder.

The iPhone 5 is expected to be announced on September 12. Some websites have the release date pegged as early as September 21, while others believe a release sometime in October is more likely.