Ferrari has basically upped the California's 4.3liter V8 engine to 438bhp. This was achieved with new exhaust manifolds and a new engine map. Torque is about 503Nm at 5000rpm and the torque curve has been made better by having higher torque output throughout the rev range.
The 2012 Ferrari California is also lighter as Ferrari has introduced new aluminium fabrication and construction methods. These new techniques have made the car 30kg lighter without any loss of structural rigidity.
Ferrari has also decided to introduce a handling kit for the California. The 'Handling Speciale' package includes steering and suspension upgrades for the car. The HS pack will make the very relaxed (for a Ferrari) California into a more driver oriented car. The HS equipped Ferrari California will include reprogrammed control software for the magnetorheological adjustable dampers. The dampers themselves will have lower-friction seals that will allow the suspension, which has springs 15% stiffer to improve body control, to respond up to 50 per cent faster to bumps. The California's steering rack with the HS pack will be 10 per cent quicker.
I suppose Ferrari, while noting that the California is liked by non-fans and has actually helped Ferrari gain a whole new category of customers especially those who used to drive Mercedes Benz SL, Porsche 911 and BMW 6 series cabriolets. But Ferrari has decided that the California needed a performance package to appeal to its more traditional customers therefore broadening the Ferrari California's customer base.