Brandon Sanderson updated his site today with some of his most frequently asked questions since the recent news that he would be completing A Memory of Light.
He gives a good description of what writing AMoL feels like to him.
Pretend you have purchased an expensive violin from a master craftsman. It probably wouldn’t surprise you to discover that one of the craftsman’s apprentices helped create that violin. The master may have had the apprentice sand, or apply varnish, or perhaps shape some of the less important pieces of wood. In fact, if you looked at the violin before master craftsman handed it off to his apprentice, it might just look like a pile of wood to you, and not an instrument at all.
However, the master craftsman did the most important parts. He shaped the heart of the violin, crafting the pieces which would produce the beautiful sound. He came up with the design for the violin, as well as the procedures and processes used in creating his violins. It’s not surprising that some other hands were involved in the busywork of following those procedures and designs, once the most important work was done. And so, even though the apprentice helped, the violin can proudly bear the master’s signature and stamp.
It’s the same with this book. What I’ve been given may not look like a novel to you, but it excites me because I can see the book Mr. Jordan was creating. All of the important chunks are there in such detail that I feel like I’ve read the completed novel, and not just an outline. Yes, there is still quite a bit of work to be done. Many of the less important scenes are there only as a framework of a few sentences. However, Mr. Jordan left behind the design of this book. I am convinced that between myself, his wife (who was his editor), and his assistants, we can complete this book to be very, very close to the way he would have done.
Wheel of Time 
