If you believe in +/- statistics (I do), the Mavericks MVP thus far is Jason Terry.
Josh Howard has been their most efficient player, with Terry coming in second and Dirk coming in third. A big reason Josh and Jet have been so good is their field-goal percentages. Jet is shooting an exceptional .597 from the floor and .625 from three-point range while hitting an average of 3 treys per game. As a team, the Mavericks are shooting .503, which is good for third in the league behind the Celtics and Lakers.
Not so surprisingly (if you've watched the games) Trenton Hassell (19.9 minutes per game) has been less than good thus far. Coming in, he was expected to be the Bowen-esque defensive stopper that the Mavs can use to lock up the teams best scorer. According to the numbers thus far, the Mavericks have been a much worse team with him on the floor. He is third-to-last in efficiency rating and is dead last in plus-minus deficiency for when he is on the court. He isn't contributing anything on the offensive end (2.2 points per game) and it's obvious by the plus-minus rankings that he isn't really impacting on the defensive end either. It's obvious that something isn't clicking with him, and until it does, he'll continue to hurt the Mavs when he's on the floor.
-Scooter Hendon, Hoops Nerd