Ok, as I think has been said before by others, the UK advert DEFINITELY says Christmas 2013.
I thought that I'd add the following as it might be missed by people outside the UK:
I live in the UK. I logged in to YT and went to this vid for example, and the GT6 Goodwood trailer/advert comes up before the video plays. At the end of the advert it clearly says Christmas 2013.
For avoidance of any doubt, Christmas 2013 definitely isn't in October or November it's definitely at the end of December 2013.
https://www.youtube.com/watch?v=oJcRMzowcaY
So there you have it, an OFFICIAL trailer which reports an OFFICIAL UK release at Christmas 2013.
That's not to say that it won't release 2 months earlier in Australia, but I'll leave you to decide whether you think this is likely.
Now, after the facts above, a bit of speculation re the above comments about Bathurst.
I am thinking personally (only my opinion) that the comments about Bathurst and October could still be valid but perhaps what we will see in October is a demo shown, a bit like the Goodwood one. It seems to me that PD are announcing each major new track at related events, Silverstone and Goodwood have been announced this way. So, perhaps they intend to show off the Bathurst track at the event at Bathurst in October?
A whole post about Australia and Bathurst and I haven't mentioned the cricket once