IMO its far and away the best driving/car game on the PS3. Its also one of the only ones that isn't an arcade racer that is drive-able with a DS. Most of the others are horribly twitchy with a controller.
Personally, I think the offline is fantastic (I've almost never gone online with it either) for one reason more than anything else - The Ring. I find it endlessly fun to pick a car from my garage, set a nice time of day and run laps @ Nurburgring.
The one thing I would dearly love GT5 to have is a few really long point to point courses. A nice "coastal" course, a mountain course, that sort of thing with time of day. twenty or thirty miles - ideally real world locales too. I would LOVE that...
