With the eminent formal availability of Windows 8 (October 26), the big “IF” that has everyone questioning its viability for mobile devices is the limited number of available apps vs. established competitors like Apple and Android.
One big hole in the entertainment app category has been the absence of a Netflix app. That hole has just been filled. A touchscreen optimized app for Netflix has just been added to the Windows Store. While it will work on any computer running Windows 8, it is clearly targeted at Windows 8 mobile devices with touch screens (tablets and hybrid tablet/notebooks).
I suspect the disparity in the number of apps for Windows 8 vs. the established mobile competitors will shrink rapidly once the new devices start to hit the streets. When Windows 8 devices become prevalent and numerous, app developers will find this market too lucrative to ignore for long.