more specifically, the problems of taking a cursor-based desktop OS user interface (UI) and expecting the Windows paradigms, complete with little icons, small click areas, scrollbars and so on, to work well without a mouse.
The article targets the HP Slate and Windows 7, but anyone who’s seen the tablet PC fail for a decade knows a big reason why. An OS written for a keyboard/mouse cannot simply be “optimized” for a stylus or finger.
You don’t even have to look at PCs to see this. Check out the Blackberry Storm to see that an OS written for a trackball cannot be “optimized” for touch either.
Touch devices need that input method close to their core, and an API to back it up. That’s why the iPad will be an incredible hit while tablet PCs will continue to fail, no matter what flavor of Windows you slap on them.