One thing that I haven't seen mentioned -- the ability to run apps designed for mobile (ARM) tablet or phone on a unified x86 desktop (on a floortop, desktop computer, laptop or server).
This may be the real story (and underlying brilliance)
of the Windows 8 offering.
This, also, appears to be what HP was planning -- put a WebOS layer on top of Windows on HP x86 boxes.
This is what Apple may be (or appears to be) positioning themselves to do with iOS and OS X Lion.
Google does not appear to have a player in this game -- neither Android nor ChromeOS are poised to deliver mobile apps on a unified desktop.
For this strategy to work, you must have:
1) a robust host desktop OS -- Win, OS X (and to a lesser extent Unix or Linux).
2) access to the host OSes internals from the layered OS and vice versa -- Windows/Metro, Windows/WebOS, Mac OS X/iOS.
3) a large base of mobile apps to run on the layered OS.
Currently, Apple appears to be in the lead -- they have a host OS, Lion, that already does much of what Windows 8 will eventually do on the x86 desktop... although Apple has done it a bit differently! Rather than run an iOS layer atop
Mac OS x, Apple has implemented much of what is needed within
I fully expect a dot upgrade to Lion* in, say, 1Q-2Q 2012, that will support iOS 5 style notifications and other constructs, and support running iOS "universal" apps within the Lion OS (full-screen or windowed -- user's choice).
In addition, Apple already has up and running App Stores for both OS X and iOS apps -- so the infrastructure is there.
Also, Apple has ported some of their consumer apps to run on both platforms (Pages, Numbers, Keynote, iMovie).
Third parties, such as Adobe and Autodesk, have already released what could [almost] be considered "lite" versions of their "pro" apps for the iPad.
Finally, Apple has a significant lead in the number and quality of mobile (ARM) apps and developers.
* When Apple throws the switch it will enable found money -- new app/revenue potential for existing OS X and iOS developers.
While MS may be on the right track with Windows 8, it may be too late when it actually becomes available in late 2012. Sadly, MS should have released "lite" versions of Office apps for the iPad... they would be in a better position to release a full version for Windows 8 -- while gaining knowledge, experience and profits in the process.
That's what I think!
In the meantime, I can hardly wait to run Find My iMac
from my iPad