All down to the manager. Ultimately he is the one who takes the criticism when things are disappointing as they were last season, so equally when the team come out flying, look defensively organised, balanced, and hungry to attack and score goals, then that also is down to the manager.
Personally I think way too much was made of last season's disappointments, and too many players were written off too quickly. In particular Vinny and Yaya and to a lesser extent Mangala. Those three have shown their levels in the last few weeks, which lets face it aren't that dissimilar to the levels they showed at times last season too. There just wasn't the consistency of the last 9 games. If we can keep that up it's difficult to see anyone in the league living with us, and in the CL there's only maybe two or three sides that could handle us in full flight and at the top of our game.