I think a lot of analysis misses this fact wrt tablets. I might upgrade my ipad2 this year or next, but it feels like it has another 2 or 3 years of life in it, and it won't go unused. The market was flooded with so many cheap Android tablets that never got their OS upgraded and were underpowered to start with. Even the first gen Nexus 7 had the bad RAM issue that caused them to become unusable after a year. That plus the underpowered ipad1 must have skewed a lot of perception on what the natural life cycle is for a tablet device.