@Caroline,
A dog that smokes, smokes, and drinks - and has a thing for his best friend's wife! For any pseudo-alcoholic college drop out living at home with a generally apathetic outlook for his future, Brian should hit close to home.
Though, I think the show is going down hill. They have essentially remade earlier episodes. Except for Louis' development into a fuller character, the show is losing it's edge. Still amusing.
My favorite minor character is Mayor Adam West. A nice jab at politicians.