Forza on PS3 is not going to happen, even if the Turn 10 contract with Microsoft is coming to an end. They will find a way to renew it. At least the last time I checked, Microsoft and Sony are rivals in the gaming world and putting Forza on PS3 is like commiting financial suicide for Microsoft/Turn 10. I don't see GT5 going on the Xbox 360 for a long time, and it would just be plain stupid to put Forza on PS3 too.
The way I see it there are only two explainations to this;
-You are a stalker - You spy on Turn 10 and Microsoft all day long without a care in the world and you decide to expose their "secrets" here on GTP.
- You work for Turn 10 - This is even less likely because if you worked at Turn 10 then you would automatically know that putting Forza on PS3 is an idiotic move. You don't even need to work for them to see how foolish doing this would be.
If Forza is going to be launched for any other console other than the Xbox, then I only see it happening on the PC for Windows because Microsoft created Windows and they wouldn't be giving their rivals free money.