I would say more end of year discounts, they were similar last year end. Even at that, most folks have been able to get a consistent ~$10k off of MSRP when including all the various discount programs at any point in the year.
My personal opinion is that North America has been a test bed for their new emissions systems on the diesel and they want to get as high a number of test subjects out there being shaken down as possible before the switch gets flipped over in Europe, big incentives help do that. Just my opinion though.
Rover - 2013 Holden Commodore SV6 Sedan
Clark - 2013 Holden Commodore Sport SV6 Wagon