The PS3 probably has another year or 2 left before Sony phases it out and focuses only on the PS4.
Likewise, Microsoft said that it will stop making games for the 360 when they have converted enough of the core games over from the 360 to the ONE. Even though no dates for this has been announced, my gut feeling is that this will happen with a flood of fan favorites from the 360 being re-released sometime around the 2nd anniversary of the ONE.