There have been many soap box paundits claiming that the desktop is dead, the sky is falling and microsoft is going out of business. These sort of claims often seem quite unbelievable although some people do like the sound of them.
To be truthful, with the exception of the sky falling, those claims may eventually become true. Just probably not any time soon. What has happened, and in a very rapid manner, is the explosion of smart phone popularity. With that popularity there has also been an explosion of smart phone operating systems.
If you were to ask the average smart phone user how many operating system they know of most of them will probably only be able to tell you of two. IPhone and Android. With Android arguably being the most popular of the two, at least in manufacturers eyes.