Beware: there is a lot of spoilery information around the Internet about The Witcher 3 right now. Internal design documents were stolen from CD Projekt Red's Google Drive and posted on Reddit and 4chan.
Speaking with Eurogamer, CD Projekt Red has confirmed the leak, urging fans to resist temptation.
"It has come to our attention that some of the production files for The Witcher 3: Wild Hunt have emerged on the internet. A portion of the files contains information about the story of the game so we strongly advise against accessing them, as this may heavily impact and spoil your future gaming experience. We also like to reassure everyone that the disclosure of said documents does not affect the development cycle in any way.
-Michal Platkow-Gilewski, CD Projekt Red
Eurogamer has browsed the files and found details of monsters, the game's plot and ending, and much more, including some internal production notes that were clearly not meant for public consumption (in reference to one character in the E3 demo: "boob physics, eye candy").
Don't ruin it for yourself!