AT&T, perhaps partly by accident, has probably created success story that is likely to become a business textbook case study classic. Its partnership with Apple has succeeded beyond the company's wildest dreams. Once a kind of also-ran in the cellular industry, customers are switching in droves to AT&T just to get an iPhone. And AT&T has wisely beefed up its network and is making massive investments to ensure its customers have a good signal in more places.
The iPhone is creating a majro change in the portable device and cellphone business, and I think the day of the cellphone is over, meaning that within five years, very few people will have a portable device that is primarily a phone. Going forward, every portable device will have to have a substantial feature set that provides many of the same functions and features of the iPhone.
Apple is probably not greatly worried, as the iPhone's potential is just now barely beginning to be tapped. The iPhone runs a version of the company's flagship OS X operating system, meaning iPhones are full-fledged computers, not just phones with a few extra features like an address book wedged in.