The more I looked at the original, the less I liked it. So here is an update. I've brightened and whitened the light, brought the foreground trees more into focus, and updated the bark textures with some much higher resolution textures found at
www.cgtextures.com. Obviously for copyright reasons Marc cannot bundle these textures with his upcoming pack, but anyone can go there and create their own bark textures by hand.
Also with this render I disabled the sun completely.
Rendered at:
Detail 1
AA: 6
GI 1/3
Catmull-Rom filter
Took 1 hour 58 minutes
The depth pass took an additional hour.