There are roughly 58 million iPhone OS devices sold through the end of Q3. Mobile analytics provider Flurry "estimates that just over 40%, around 24 million are iPod touch devices." Most of the iPod Touch users are younger than iPhone owners -- many parents have bought them for their kids as gaming Devices.
According to comScore and AdMob, a sizable majority of iPod Touch users are younger than 24, while the largest chunk of iPhone users is over 25.
Accordingly the point is that Apple is not only extending the iPhone experience to those who don't want to switch to AT&T (like me) it's building the next generation of iPhone buyers. Flurry echoes this:
As all industry eyes look to the iPhone, the iPod Touch is quietly building a loyal base among the next generation of iPhone users, positioning Apple to corner the smartphone market not only today, but also tomorrow. In terms of Life Stage Marketing, the practice of appealing to different age-based segments, Apple is using the iPod Touch to build loyalty with pre-teens and teens, even before they have their own phones (think: McDonalds' Happy Meal marketing strategy). When today's young iPod Touch users age by five years, they will already have iTunes accounts, saved personal contacts to their iPod Touch devices, purchased hundreds of apps and songs, and mastered the iPhone OS user interface. This translates into loyalty and switching costs, allowing Apple to seamlessly "graduate" young users from the iPod Touch to the iPhone. For OEMs hoping to challenge Apple, we believe an even greater sense of urgency must be adopted.
Flurry points out usage of the iPod Touch is a huge part of the overall audience they're tracking and a major component of the social networking audience, which is comprised of a slightly younger demographic: