I really like this photo. I like how the gray and the contrast really set a mood to the whole photo.
One thing that did kind of bother me was that the dog's left eye kind of blends into his (or her?) fur. I saw in other photos of the dog, that the eye is blue and black, but maybe you can lighten it slightly in photoshop (dodge tool?) or whatever editing software you use. Just a thought.
I like the position of the dog in comparison to the houses and ends of the yards (I like how the top of the dog's head isn't in line with the edge of the yards/driveways).
The bluriness of the houses in the background is a nice touch, too. It keeps the focus more on the dog.
I know it is sometimes hard to see everything that is in the shot before taking it, especially if it is a quick capture the moment shot with animals, but the car in the background with the headlights on does slightly take focus off of the dog, though not enough to really matter (worth mentioning though).
I like how the dog is raising his paw, giving the impression that the dog is walking forwards. I don't think the photo would have as much of an impact if the dog had his paw down on the ground.
Quick idea...what if you lighten up both eyes and make them light blue, while keeping the rest of the photo the same gray color? It might look cool. Just a thought.
Overall, it is a great image and the small problems that I mentioned are not big enough to impact the overall coolness of the photo. Good job.