My main interest in W8 was the "Windows to go" feature -- this really works -- you have a fully working Windows running from a USB stick (or better) an external USB disk device -- and I mean a FULLY working windows system -- not an install mechanism or a boot to your internal HDD's. You can disconnect every disk in your computer and boot up the windows to go system via a USB slot.
I have no problem whatsoever with W7 -- for a desktop OS it really can't be bettered --even though loads of Linux distros have improved over the years - but it doesn't have the "To GO" feature -- pity as this would be a W8 Killer app.
I don't find any problem with MS launching a tablet / mobile phone OS -- after all Google with Android started from scratch -- and horrible it was too.
Android is rapidly maturing into a decent mobile phone OS (although who ever thinks of those names -- latest version ICS -- "Ice Cream Sandwich" for gawds''sakes).
W8 has to decide whether it wants to be a desktop or mobile os. No way Metro with 35 km of left scroll to find your application will this ever get NEAR a corporate workplace.