Anyone who's followed The Witcher 3's development from the first teasers and trailers to the finished product has likely noticed not-quite-subtle changes to the graphics—and definitely not for the better. A NeoGaf poster whipped up a quick comparison, and the differences are rather stark, I'd say. And this guy agrees.
Eurogamer asked developer CD Projekt Red about the graphical downgrade. According to the team behind the game, the eye candy in the early tech demo would have been too difficult to scale up to the full game world. They cite a few specific examples, and they suggest difficulties "regardless of the platform."
The official statements contradict those made by an unnamed insider who detailed the graphical downgrade for What If Gaming. That story claims CD Projekt Red scaled things back because it couldn't realize its original vision with the relatively limited horsepower of current consoles. It's a decidedly different perspective on the events, and it's dredged up old quarrels about console peasants and their master races.
The Witcher 3 is still getting lots of love from both gamers and press alike. Despite the graphics not being quite as stratospheric as expected, the game looks like a success. And, hey, any post-2000 game that dares to include a map, manual, and thank-you note in the regular physical version deserves respect.