People, just because the American version doesn't have Holden and Ford mentioned doesn't mean that they won't be in. The worst-case scenario would have to be that (this will p*ss off some folks if it happened) non-American versions of GT4 get Australian cars and an even worse case scenario- Bathurst.
I'm not usually the optimist, but I say be optomistic. Remebmer, the game doesn't come out in America until maybe a few more months. These few months feel like forever, I know. But at least it's better than saying it will come out in 2006 or 2008. So keep up hope, alright? 👍