Little buster looks like my friends dog and he is a shihtzu. However, when I looked up a picture of one they seem to have really long hair. Maybe it is optional/personal preference whrether they get their hair cut or not!!
As hugnie21 says it is a cross between a shih-tzu and a Bichon. That's were the curly coat comes from. Shih-tzus look totally different when they have long coats, however it is not always pratical to keep them long. I have two and I keep them clipped.