The nerd talk about Windows vs the World seems to miss the point that users are no more interested in their operating system than their car engine. Any OS is at best a necessary evil! Only applications matter. Retraining - however 'trivial' - costs a fortune and untold miseries. Stability, possibility of running any old application (try that with the Mac!) and plenty of people to ask for help if stuck are the reasons for the dominance of Windows.
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