I have figured it out.
The end of world of warcraft, the final cutscene after we beat the last boss that blizzard let loose upon us, we'll be seeing a real life zoom out of a book.
As the camera keeps zooming out, we can see that the book is resting on Knaaks' lap, as he smiles into the camera.
He then closes the book, takes a deep breath and says "And this is how the story would go if over 10 million mortals would gain enough power to even overcome the titans."
A week after the first guild downs said last boss, Warcraft 4 is announced, featuring how the story would continue after Arthas mounted the Throne in Icecrown without player interference.