I am not worried,
It took years for mainstream users to switch from XP to Win7.... there is absolutely no way they will be interested in Win8.
I also see most of my comrades from MS .net development jumping ship to do cross platform development.
MS also made a major error in thinking they can defeat Apple's inertia in the table market.
This is what I am seeing in my circles
-Business professionals who need desktop software -> Already have windows 7 now (They are not even considering Windows 8 for any other reason that Win7 does what they need. Most skipped Vista and went from 2000/xp to Win7 and will remain there for at least 4 years)
-Media consumers -> Already have an iPad (most) / Android (less) and have no need for, or interest in a Win8 Tablet.
-Freelance developers (like me) are switching to cross platform toolkits, because they can't make money on anything but iOS / Android (this demographic is growing rapidly as more corporations toss their dedicated developers into the streets)
-Techophiles: Of the people who really don't have a reason to get upgrades other then they like being cutting edge... I think it is about a 10 to 1 ratio of hatred / like for Windows 8 from what I am seeing.
I've been pointing these people to PC BSD and they are all distracted by it, probably enough that they won't put up with all the bullcrap built into Windows 8.
It's kind of sad really, because I was really looking forward to the MS store, but I confess I loathe windows 8, and am classifying it in the same category as Millennium... basically it's a hairbrained attempt at a "do everything" OS that is going to ruin MS.