We're now apparently just weeks away from Apple's (Nasdaq: AAPL) new iPhone.

AT&T (NYSE: T)? Check.

Verizon (NYSE: VZ)? Check.

Sprint Nextel (NYSE: S)? Why not?

The Wall Street Journal is reporting that Sprint will become the next major stateside carrier to offer Apple's iconic smartphone when the iPhone 5 hits the market in October.

The news has been a long time coming, though Sprint users may want to be careful about what they wish for.

Sprint has resisted nixing unlimited data plans for new customers, the way that AT&T and Verizon Wireless have. But could that simply be because its network hasn't been overcome by data-sipping iHogs?

Sprint has often marketed its pricing advantages over AT&T and Verizon, but cynics can argue that Sprint has paid the price. AT&T and Verizon are consistently profitable, while analysts don't see Sprint turning a profit until 2013 at the earliest.

This does matter, because iPhones aren't cheap. With Apple commanding roughly $650 for every new iPhone, a carrier needs to subsidize hundreds of dollars that will hopefully make back during the two-year life of the contract. Can Sprint offer the iPhone without jacking up its rates or abandoning unlimited data plans?

If Sprint can miraculously make the numbers work at its current rates, it's going to win over more than just existing customers due for an upgrade. Verizon and AT&T customers will follow the savings -- as long as Sprint's network is up to the task.

Even if a Sprint iPhone makes it easier for regulators to clear AT&T's pending acquisition of T-Mobile, getting the iPhone could be a defining moment for Sprint. As of right now, the company is a distant third in the wireless market, with roughly half as many accounts as AT&T or Verizon command. If Sprint can hold its ground without buckling under pricing or network-reliability pressure, this profitless yet promising telco giant could close that gap in a hurry.

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