In an interview over at Gamecrate Naughty Dog's co-president, Evan Wells, talked about the history of the studio, with focus on the book The Art of Naughty Dog which is due out October 14.
When asked how Uncharted 4: A Thief's End was doing, Evan replied:
"It's coming along nicely. We've been hard at work since E3 and all I can say is that we'll be having some stuff to show you very soon."
When pressed on how soon "very soon" is, he simply said: "Very."
We know form experience that developers tend to have a different perception of "soon" than us, but hopefully this means we'll get to see more from Drake's next adventure this side of new year's.