I don't quite get this forward compatibility concept.
As I understand this, PS4.5 is a new PS4 with a beefier APU. The console is basically the same, so it's 100% backwards compatible. But how can a game console be forward compatible? If you make a game exclusive to the PS4.5, it won't work in the PS4 because it won't have enough ram, the GPU won't be fast enough or whatever.
What I understand makes the PS4 forward compatible is Sony forcing developers to make PS4.5 games that also work on the PS4. What Sony can't enforce is the PS4 version being good.
4-5 years I can stand, supposing every new PS will be backwards compatible and there will be a cross gen period.
Well there is going to be a weaker hardware and a beefier hardware, I suppose developers will have to optimize for each hardware independently even if they share the basic architecture. Won't they?
We have 2 consoles this gen that feature the same Apu but one has one pool of memory and a beefier GPU and the other one has ESRAM and a weaker GPU. And you can clearly see when developers target one or the other. It's very rare that a developer gets most of both of them, I expect the same from this PS4/PS4.5 situation.
Obviously the differences in architecture and power between PS3 and PS4 are much bigger, but the basc premise still stands. There are 2 hardware configs. Developers are going to have to target one. At first it's going to be the PS4. Bit, in time, as hardcore gamers and big spenders switch to PS4.5, developers will switch their efforts to PS4.5 too.
If we wanted a PC life cycle, why wouldn't we buy a PC? Games are cheaper, all PCs are backward-forward compatible, online is free, you change generations whenever you want...