DirectX 11 is coming sooner or later. They probably won't officially drop support for PS3 for a long time yet but at some point the PS3 version will start to get left out of major "cosmetic" graphic updates or get only scaled-down versions. People will start to migrate to PS4 once it becomes more affordable, and PS3 users will dwindle naturally. Support can then officially end once the PS3 user count drops below a certain threshold, so backlash is reduced to a minimum.

It won't happen within this year or probably even the next, but sooner or later it will stop making sense to support the game on two very different Playstation platforms.