I have to say that I'm impressed, the improvements in lighting, shadows and texture quality are great. Also it's the first GT game with good looking trees :O
Improvements in car handling are also immediatly evident, the car's weight visibly transfers thanks to the new suspension system.
Now of course let's be real, this is not a full new game, it's just the best GT game the PS3 can offer. People expecting a next gen leap on the same platform are of course going to be disappointed.
I was expecting basically a data disk so I'm impressed, but I'm not going to buy this at full price, I think I'm going to wait for the definitive PS4 version with all the DLCs included.