While my dad is technical, he isn't necessarily a computer expert. He lives in another state where I live and I had no input over his OS choice at all, so I see his experience as typical of the masses with some computer knowledge. He went ahead and upgraded to Windows 8 and basically all went well.
The first thing he did after installing Windows 8 was complain that it took him a long time to figure out how to power the computer off. The next thing was to install that utility that gives you back the start button and also boot into the desktop. I didn't tell him about it - he just searched around and installed it himself. He is very proud that his computer now looks and acts "just like" Windows 7 (although I have to disagree in that the Windows 8 desktop looks fugly compared to Windows 7).
Personally I have Windows 8 installed on my desktop and hate the tile UI. I find it annoying since it tries to force me into this one-app-at-a-time mindset that I just don't like. I gave it a long time now but it's not growing on me. It doesn't belong on the desktop with multiple monitors, so please keep it on the tablets thanks a lot.