Why are uninformed FUD comments like this getting modded up? The blogpost clearly states that WOA devices will be unequivocally labelled to strongly distinguish them from traditional x86/64 devices.
WOA is not an attempt to replace Windows with a gimped version of itself. It's meant to be another member of the Windows family, like Windows Server, Windows Phone, etc., that extends the basic Windows paradigm to devices where it does not have significant market share. It is basically a rearchitected Windows CE that takes into account the rise of iOS.
iOS is derived from OSX, but you wouldn't expect to run an OSX application on iOS. So Joe Q Public is already primed to the idea that top-tier desktop applications won't run on WOA, and from reading the article, it seems that the marketing of the tablet devices will make that abundantly clear. Windows 8 Desktop is the successor to Windows 7 and WOA is something different, a competitor to iOS that has a Windows-esque look and feel.
Where WOA claims to have an advantage over iOS is, first, that it will allow users interact with the device with a traditional desktop paradigm, if they choose. Secondly, WOA apps, unlike iOS apps, will be also able to be run on your traditional desktop/laptop, making for a much more integrated total experience. And thirdly and most importantly, MS Office.
However, if the concept of being able to "up-run" your tablet apps on your desktop proves fruitful, there's no engineering reason why Apple couldn't do the same thing. And of course, once Apple did do it, suddenly up-running your apps would be the most awesomeish thing ever.