This car is more commonly known as the Holden Monaro. GM brought this up from Australia from 2004 to 2006. It was a cool car but Americans didn't buy many of them(because we're idiots), and so it got cancelled. This was essentially replaced by the superb G8(Holden Commodore) in 2007...which will also be cancelled in 2010 after another short 3 year run.
The dealer had at least 3 of these on the lot.
This is why we can't have nice things.