How long until the major third parties start abandoning PS3?

Its already begun, the games are going multiplat and there are no new major third party titles being announced which aren't multiplataxt113

That's not the same as third parties "abandoning" the PS3 though.

They already are, they are doing what they should been doing and doing multiplatform. In today's market the only way to make money is to go multiplatform.

To describe games going multi-platform as abandoning the PS3 is too strong. Atleast it is still getting the games. Third parties are still supporting the PS3 and aren't abandoning it, not yet anyway.