Apple's Strategy of Planned Obsolescence
CrunchGear's Seth Porges muses on Apple's strategy of planned obsolescence in product development. iPhone falls into this category, much like its musical cousin - iPod. This is the primary reason why you won't see user replaceable batteries in either product. Apple doesn't want you upgrading your device, they want you to upgrade to a NEW device. This strategy was widely used by auto makers in the 1950's and 60's. Each year the big three would roll out new models designed to make last years model look obsolete, fueling consumer buying. It may have worked with iPod, but I doubt this will work for iPhone due to the inherent entanglements of wireless carrier red tape.