From Brandon Sanderson...
I'm almost through with the third, and most difficult, edit of the book. Once I get this one done, it should be pretty smooth sailing for the book. (Though I'll have to be doing revisions as I tour this week, which is going to make for a busy time.)
The book stands at almost exactly the same length as the first volume, despite my (somewhat sincere) attempts at making it shorter. Release date is set right now for early March. We played with both November this year and January next year before finally settling on March, just to make sure I had enough time for revisions.
I realize this book has been a long time coming. My dedication to finishing the Wheel of Time with minimal delays meant that I had to push off Stormlight for a few years. Now that I'm done with Randland, you can expect Stormlight books to come way more regularly than they have so far. I appreciate your patience.