Followed by....
Followed by... "The death of the PC has been greatly exaggerated."
Notebook PCs, and even desktops, I just don't see sales falling off a cliff. Decline? For sure. Death? Well, I don't think so.
Even for desktops, there's so many business uses where the person is at a desk or workstation, the computer is stationary (in fact for discouraging theft it's far less likely to walk off). A similar-spec desktop costs less than a notebook, and much faster desktops are available if the goal is raw processing power.
As for notebooks, there's still so many uses where the software available on Android and especially IPhone would be far too confining. People have already gone over these in other comments, and the article touched on some. I would find the typical rubbery little bluetooth keyboard pretty unsuitable for more than a little typing too (I'm a serious keyboard conoissuer though). Just as with the desktops, decline in sales? I won't be surprised. Death? Doubtful.
I do find the idea of saving serious power by running Linux on ARM instead of Linux on Intel very appealing though.