Why have newer, more efficient technologies not been adopted faster and by more people? We can learn by looking at the Technology Adoption Life Cycle (TALC). This sociological model places consumers into five 'adopter groups.' Those groups follow a bell shaped curve in the adoption cycle of a particular technology. Geoffrey Moore also speaks of a 'chasm' that technologies must cross in order to be assimilated into the culture. According to Moore, the chasm occurs between the Early Adopter and Early Majority groups of the TALC.
Dovetailing with the above theories, there is also an acceleration over time of the creation and availability of new technologies.
Although the TALC is helpful, it doesn't speak on the amount of adoption time involved with each new technology. With the accelerated availability and development of newer technologies, it could in turn be inferred that the TALC is accelerated as well. Each technology moves through this adoption process, but the cycle itself may take less time.
Back to the question we first posed, how do Kiosks stay viable in a world that is being proliferated with mobile devices? Two words, physical location. Kiosks are placed in highly trafficked locations and offer a physical means for both vending and advertising. Vending of a physical item in real-time: whether you want to print a paper ticket/coupon, rent a DVD, purchase a product/good or check in at a location, those tasks can all be accomplished seamlessly using a Kiosk. There is also a physical presence a Kiosk provides, consumers can see and use it 'in the wild' so to speak. This way Kiosks can work as a bridge to the mobile experience, either by signage on the physical Kiosk or advertisements via the interface. You can inform consumers about mobile functionality that can be coupled with a Kiosk, functionality that they may not have known of otherwise.
Kiosks are still an important piece in this emerging mobile world. It will be very interesting to see how both the mobile and Kiosk experiences intertwine and evolve in the years ahead.