It was a close call between Skyrim and Skyward Sword to me, but in the end, I gave my vote to Skyrim, since the PC version is the best Elder Scrolls game ever made and it can only get better as support for it increases over the next months, thanks to the Creation Kit.
Edit - A shame Dark Souls wasn't on the list, as my vote would have gone automatically to it. It's my personal GOTY and, on par with Demon's Souls, one of my favourite games of all time.
Current PC Build
CPU - i7 8700K 3.7 GHz (4.7 GHz turbo) 6 cores OC'd to 5.2 GHz with Watercooling (Hydro Series H110i) | MB - Gigabyte Z370 HD3P ATX | Gigabyte GTX 1080ti Gaming OC BLACK 11G (1657 MHz Boost Core / 11010 MHz Memory) | RAM - Corsair DIMM 32GB DDR4, 2400 MHz | PSU - Corsair CX650M (80+ Bronze) 650W | Audio - Asus Essence STX II 7.1 | Monitor - Samsung U28E590D 4K UHD, Freesync, 1 ms, 60 Hz, 28"
