Being a stupid American, I had to go to Wikipedia to learn that a Holden Commodore is called a Pontiac G8 up here.
"
Internationally, the Commodore is again badge engineered as the Chevrolet Lumina and Chevrolet Omega, along with its new export market in the United States as the Pontiac G8 (discontinued as of 2010 along with the Pontiac brand)."
Whenever I see a G6 on the road, it's nicely-sloped rear window always makes me do a double take. It looks similar to the ECOmmodore.