It would make no sense...
And i'd feel sorry for them: how many billions did they already lose in the last three years?
The Blue-Ray has a very limited success, and the PS3 profits can't compare to the old PS2 profits, both on the hardware and the software side... PSP is not an important factor, and if they release an (even more powerful) PS4, no dev in this world will take the risks to do even more expensive games, for an even more limited userbase...
Plus, the consumers would feel cheated, not so long after the release of a PS3 Slim and a brand new controller that won't have the time to (finally) become real success... a very bad idea all the way...
This would simply mean that Sony's gaming division is commiting suicide...
And then, the situation would be quite clear: one american console vs one japanese console, Microsoft vs Nintendo...
The american console would have nearly all the western games, plus some of the best japanese games, and the japanese console would have all the japanese games, plus some of the best western games... and any gamer will have a good choice, and will even have the possibility to easily afford both, to be able to play any of the best games on the market...
It's a win-win situation, and an even more competitive market than a 3 consoles race... and it would also be easier to manage cross-platform games for anyone in the industry... so why not...
In fact, it would then mean: back to the old Nintendo vs Sega, but this time with an american opponent with its usual monopolistic agenda, on the PC scene just as on the console scene...
No need to say which console i'll buy then, as anyway, japanese games have always been my favourites, and i don't trust anyone with a collection of "red rings of death" plus a monopolistic agenda... :)