This year Ferrari has two wind tunnels so you are all aware, they purchased Toyotas Wind Tunnel in France (considered to be the second largest Formula 1 wind tunnel) as well as their own tunnel at Maranello.
The difference from this year to last year is that the car is now being tested in a tunnel that is correctly calobrated and the information correlated to the engineers and technicians is accurate.
Two wind tunnels, lots of components = a lot of variable testing = Championship winning car.
Lets wait for Melbourne but if Ferrari mechanics as well as engineers are smiling with Massa they must be on top of something after the endless work (rumoured they pulled a 72 hour rotation shift on new components and internals).