Max looks very interested in something. Ok...who do you have dangling on the fence? :-) I know I'd think twice about coming over seeing him!
From a technical standpoint the photo is sharp where it counts (his eye) and good detail in that immediate area and lower neck. Considering how this composition brings the dogs "face" in pretty close, a smaller aperture with deeper DOF may have brought the score up some. The pole in the bottom right is a slight attention grabber.
The more I look at this shot, the more I like it. At first I was not sure, but after studying it, I appreciate the details you have captured here. It is sharp in all the right places, the colours are deep and rich. Clever angle too. Well done 8