Microsoft is about to take on tablets in a big way, first with Windows 8 and the mobile version Windows RT. The new OS combined with Microsoft's own tablets, the Surface line, can totally disrupt the tablet segment.
While new versions of Windows usually take a while to get adopted en masse, the bring your own device (BYOD) movement may accelerate that adoption. The Surface tablets are natural fits for the BYOD scenario with consumers needing a work tablet that also does fun stuff. If Microsoft plays this correctly from a pricing standpoint, the Surface and Windows 8 can shake the tablet segment like a kid clearing an Etch-a-Sketch.