Sony continues to sell the PS2. There have even been new game releases for the PS2 as recent as this year (2012). I see no reason why they wouldn't continue to make and sell the PS3 regardless of what they have coming next.
I think new consoles are really expensive proposition for both the platform provider and consumer. I have yet to feel PS3 is even close to being over due for an upgrade. Nobody has seen any software that would truely benefit from being on a PS4 (or XBox Next).
The only console that needed the upgrade is getting one (Wii --> Wii U).







