Not running Windows per se, but the Microsoft RDP client on Android linked to a Windows PC works very well.
I don't think we'll ever see the Windows kernel running on the Exynos chipset TBH, at the least it would require virtualization or emulation that would require a lot of coding and in any case Windows would place a much larger overhead on the processors than Android or Linux.
Windows RT, the Microsoft "equivalent" of Android (i.e. designed to run on a low-powered chipset), has not been very well received due to its much reduced command set. It looks like Windows desktop, but it cannot run full-blown Windows desktop applications.