Just in case you missed the news at the end of the conference yesterday, the rumors are all true: Sprint is indeed carrying the iPhone 4S, and a spokesperson for the company confirms Sprint will offer an unlimited data plan for iPhone users. That means if you were one of the many users (myself included) who switched away from Sprint for AT&T way back when the iPhone debuted, you can now consider the option of switching back, at least later on this month when the iPhone 4S debuts.
But you may want to think about that option carefully. While Sprint is offering an unlimited data plan on the CDMA 3G network, that network is relatively untested for iPhone levels of traffic, so there may be just as many issues there as AT&T and Verizon have had with the iPhone in the past. Yes, it's possible that fewer customers will be using Sprint's network, but the iPhone drags a lot of data down, and the iPhone 4S will call for and send data back and forth even faster than the current model. Customers who run over to Sprint may not find the grass is as green as they thought. [It's also worth noting that both AT&T and Verizon offered unlimited data plans for the iPhone at launch, but both companies quickly rescinded them and rolled out tiered data plans. --Ed]
Still, options are always nice, and a three-way iPhone battle between US carriers will be interesting. AT&T is obviously still the grandfather of running the iPhone, but Sprint may set its targets on Verizon first, making for some real competition between those two services. We'll see how it all plays out.