The G6 is supposed to be in showrooms by the end of the summer, so I dont doubt that they are close to producing a ready to sell unit. I imagine that the same thing is going on right now at the Lordstown plant where the Chevrolet Cobalt will be made and in Oshuwa where the Buick LACROSSE will be made. Bowling Green is probably getting ready to shift over to the C6 soon too.
The Grand Am was/is Pontiacs best selling car, so I dont doubt that the G6 will be produced in some serious numbers, I dont know if it will challenge the Accord or Camry, or Impala(which is number 3 and climbing

) but I think that the G6 has the style and pricing to make it one very hot car.