Yes, there’s now a working Wii U emulator for Windows 10. The program is called Cemu and was shared over on the GBATemp forums. As you would expect it runs Wii U titles at a resolution of 1920×1080 and features full keyboard controls. The emulator is still a work in progress as there’s no audio and certain games crash, although it can run games such as New Super Mario Bros U and NES Remix. However, certain games aren’t working such as Super Mario 3D World. Nintendo clearly won’t be too happy about this development.
Thanks, cheatmaster30 anon.