I think it'll just be gt4 for the ps3 for the moment.
There's nothing wrong with releasing it again on a new platform - with saved games being compatable etc. There's no net play so you dont have t worry about games compatability.
All it would take is texture reworking, system optimisations and wham, a great game in a year or so - but call it GT4, not gt5.
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She says brief things, her love’s a pony
My love’s subliminal