Man, Asymco is killing it these days with their mobile analyses:

Finally, looking at the pure smartphone vendors RIM and Apple, the picture is nothing short of astonishing. This before-and-after share-of-available-profit chart shows that the two entrants went from about 7% profit share to 65% in three years.

Disruption is the diagnosis here. The incumbents were caught in the headlights. Disruptive innovation leads to asymmetric competition and this is what we just witnessed. History has shown that the shift of profits is usually the last stage of disruption and is usually irreversible because the change in business models cannot happen at the rate of change of profit transfer.