For whom? Companies might make more money selling mobile devices compared to desktop/laptop PCs but that doesn't equate to the inane statement oft repeated that "desktop computing doesn't really matter that much anymore".
Desktop (including laptops of course) is where 99% of the world's actual office, accounting, design, writing, programming, editing etc, computing based work is happening.
Agreed. Try typing out a dissertation on a tablet (no external keyboard or mouse to compensate) which has an approaching deadline.
I don't think the old stereotype of "consumers" as some sort of purely passive livestock is especially useful any more. Clay Shirky's old but very readable "Here Comes Everybody" makes a similar case at much greater and more articulate length.
BWAHAHAHAHA!! Thank you. I needed that laugh.
Laptops and desktops will always be more powerful than mobile devices, therefore there will be users who want the option of having said extra power. Even if you could, say, run AAA games on a mobile device, the interface would be awful for most of them (eg FPSes).
The vast majority of actual 'personal computing' is phones and tablets. PCs are content creation devices.
Asides from Android obviously not being the traditional stack - no glibc, no KDE or GNOME - AOSP isn't very useful compared to semi-proprietary Android. We could also say that CMU Mach / FreeBSD won the desktop because iOS and OS X use them.