When you first see this, it looks pretty good. The face is the main feature, and the eye is drawn to it.
Anatomically, the ear seems to be placed in a pretty good place from the nose, though the eye seems to be a bit further back than what would be normal. The mouth is also in a strange position and confuses the viewer further whether the subject is looking directly at the viewer (the mouth), is partially looking at the viewer (the eye), or looking to the side of the viewer (the nose and ear). The head seems a good size compared the rest of the body, however.
Moving on, the two front paws seem an appropriate size and all the joints seem to be positioned correctly. The furthest away paw pad seems to be drawn pretty well and is also detailed, and the paw nearest to the viewer also looks good but it does seem as if it only has three toes, though it appears as the other paw has four toes.
The back legs seem to be bent at a strange angle, though they are still a nice size and proportionate. Perhaps it would look better if the leg was moved 45 degrees or so counter-clockwise.
The tail is nicely drawn though is too large for the body (if stretched out, it looks as though it would be the same size as the body) and could do with some size reduction.
Overall, this is a nice piece which is generally pleasing to the eye. The lines (at times) seem a little messy, but that is forgivable when with the rest of the artwork.