His movement off the ball isn't good enough. In the game today at one point I think Vertonghen had no-one to pass to - all Huddlestone had to do was move laterally five yards off the ball to make an option for him and he would have been able to keep play rolling rather than hit it up field in desperation. He isn't intelligent enough on the field, no matter how many 40 yard balls will try to cover that. Defensively, he's too slow to get back into position and react to danger, which leads to him making mis-timed challenges and bookings.
He's in the shape of Michael Carrick but has never lived up to the hype and I don't think he ever will (please prove me wrong).
I think this is true of a lot of our players to be fair and something that really separates the top 2/3 from the rest of the league. Great teams always have options.