Focus and depth of fied are great. Nice and sharp everywhere, which is needed in this picture. The detail and texture of the sky are fantastic
The way the cloud formation seems to mirror the shape of the tree is amazing. Although it is extremely bright to the point of burnout at the top of the trunk, it works here because the tree then looks almost as if it were on fire.
The trunk of the tree does bother me a little. It seems a bit odd. If you follow the line down from the limbs, it isn't a smooth curve like most trees. It looks almost pixillated like it has the jaggies from a lower res rendition blown up. Since it happens in several places, I don't think it is an illusion, or a trimmed off limb. Looks almost as if it were assembled.
I like the color of the sky, but wonder how this might have looked in color if it were one of those majestic blazing sunsets we get now and then.
Overall this is a very good photo, one I could see hanging in a gallery. Congratulations on a well deserved top 20 finish.
Great placement of the tree and I like the colours. Not too fond of the overprocessed smoothness of the sky, I'd like to see a bit more detail in the clouds, but still a top notch image.