Bingo. SOC, screen and battery define the longevity of the device. Being able to upgrade those piecemeal moved mobile devices closer to that of the desktop PC (frankly if we could move the CPU onto a daughterboard i would be dancing with joy).

Also, screens are what most often break on a device, because glass don't deal well with sudden applications of force. Making them modular with a defined attachment system would be godsend for many butterfingers and parents.

All in all, what they are presenting now is things that can be done USB, WIFI or bluetooth.

At least the modules will get power from the case (I assume) so they won't all need their own batteries and chargers. That could be handy.

Given the economics of today's limitations, yes, that would be.

But if you knew, for example, that your camera could be used with your next two CPUs, you might make a longer term investment in a higher-quality camera.

I think OEM's pushed Google a bit, not wanting to kill the upgrade cycle. One sign for that is the non-removable battery - which is easy to do technically.

I'm not so sure. Look at the module sizes the largest one at the bottom is still much smaller than modern batteries. If the battery had to be in one of those they'd have issues with longevity. Maybe allowing additional packs but trying to fit a main battery into it is going to require compromises somewhere.