PC manufacturers were thrown off by Windows 8 and its new touch-friendly face, which has given the PC industry what it needed to bring the PC forward into the mobile device space. The PC's long term success hinges on its ability to evolve, both in form factor and functionality. Boxes have largely given way to all-in-ones, laptops to Ultrabooks, and so on. Innovation often equals experimentation, and so PC makers have been throwing various PC designs against the wall to see what will stick. There's no question the tablet is the next evolution, but the PC is having a hard time finding a tablet form factor that truly embraces the versatility of Windows.
The current crop of devices tend to make tradeoffs, some due to hardware and some due to the maturity of Windows as a legacy desktop OS. The modern side of Windows 8 is best enjoyed on a tablet, while laptop form factors tend to fare better with legacy programs and the desktop in general. Naturally, given Windows' dominance over the past 15 years, slate tablets running Windows RT haven't had the best of luck competing with devices from Apple and Android and their vast app stores. X86 slates, like Microsoft's own Surface Pro, offer the full PC experience like backwards compatibility and performance, but currently at the sacrifice of battery life.