Demand,
You say this about Acer's build quality as if it were something new. Frankly, I was shocked by the Iconia W700 because it wasn't built like garbage. But yes, Acer has classically had shoddy built quality. The thing is, they had shoddy build quality in the past, being the clear-cut budget machine on the shelf, and they did just fine. Now all of the sudden, same bad build quality and even a few well made items and... They're doing badly all of the sudden?
Simple question with a simple answer - what's changed? Now, I'm not shoveling all the blame on Windows 8, but some of it has to lie there. The computing world is changing and mobile devices are filling roles that used to be filled by PCs so people don't need to buy PCs to do PC things. What's more, the PC upgrade cycle is slower. No question, both of these things contribute but the answer to "what's changed" is, at least in part, Windows.
Any way you cut it, Windows 8 was made at least in part with mobile in mind. For people using straight up non-mobile PCs, this has turned a lot of people off the OS. I've met casual users who look at it and say "What the heck is this and why do I want it?" and we both know the vitriol it inspires here at Tom's. If you want to pretend like this isn't at least part of why PC sales are slowing, that's your business, but... While an OS isn't solely to blame for slowing PC sales, an OS that people really want to buy certainly could help them out - and I don't think Windows 8 is that. May change when people start using mobile touch screen devices with it more but for now? I doubt Windows 8 is helping PC sales much at all.