@CaliBoy: Ah... hope remains then.
Personally, I'd be willing to wait an extra 2 years or maybe more for GT6 if it meant some upgrades to GT5 in the form of DLCs. Standard cars upgraded to premium, and maybe a few cars from GT2 such as: Espace F1, PT Spyder
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, Coppehead/Concept Car and LM Edition, the better Proteges and Pulsars, the many "tuner" type prize cars, various Tommykaria tuners, etc. etc. Where'd all the good cars go anyway? Oh that's right, they became Skylines, Miatas, RXes, 3000GTs, and of course Kei cars. (That reminds me, I'd like a lot less redunant/generally wrothless cars in GT6. But that's another story.)
Maybe revive some tracks from earlier games - I for one would go for Red Rock Valley, Tahiti anything, Rome 90's (and Rome Night - loved that course), Green Forest Roadway, Grindelwald, Smokey Mountain, aaaaaaaaaaaand Seattle Short. I loved all of those, and I'm probably forgetting something here.
Oh, and a livery editor. Can't forget that.
Like I said, I'd be willing to wait a looooooooot longer for GT6 if some surplus content was provided for GT5. Anyone agree?