Sony isn't a big player in the USA, yes this is very true. But they are the first of the old school Japanese folks to follow some of the American old school crew in dropping the PC format way way down in production volume.
More will follow. PC is crashing now --- and Apple is certainly rejoicing.
This graph is USA only and it shows Apple tablets and phones picking up almost all of what PC is dropping. Apple is boasting they took over the sales lead in the USA last month (figures not verified yet by Microsoft, of course). Note that Apple laptops/desktops are flat to previous years, no real growth at all.
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Android/Chromebook is a different threat to PC and like Apple they show strong growth last year, growth that
if it continues will put Windows laptop sales in a majority danger within a year or so.
Certainly, if you lump Apple/Chromebook/Android-all-in-ones together world-wide, they already outmass Windows PC/laptop sales for the first part of this year already. Windows is not winning anywhere anymore.
This is a fuzzy USA/Britain type graph that shows Apple's installed base as still being bigger than the installed base of Android (all flavors). This is talking about the "total installed base", not current sales. Android is selling in today at 83% of the total sales currently going on.
Take this almost equal Apple/Android graph and lump it against the Apple/Windows graph earlier --- Windows is in real trouble.
Microsoft likes to say their sales share is increasing (and it is, technically compared to itself last year) -- but compared to the total market growth amount they are losing ground very rapidly, generally to Android worldwide (except in the USA where Apple still picks up much of what Windows drops).
Win 9 MUST be an instant hit and it must be able to run on ARM chipsets. Or if MS needs another two year reboot due to screwing up yet again they might as well hang it up, they won't have a "current sales" market share left any more to defend.