After about 30 minutes, I’m very impressed. You can really alter your line with throttle, lifting to tighten up, slowly getting on it to push wider. Just like in the real world, I’m having much more fun with the RWD cars than the AWD cars. There isn’t enough challenge driving the 911 Turbo. 
The one thing I miss from GT4 was the ability to have the TCS set to 1 (range of 1 to 10) to make getting rolling with a high powered car easier. One gave you plenty of wheelspin to rotate in the corners, but you didn’t sit there fighting to get moving from a stop/slow corner. Hopefully we’ll have more than “on/off” in the full version. Right now I have ABS on, TCS off, and stability off. It makes for some careful trigger finger action with the high powered RWD cars. 360 triggers > PS2 buttons for throttle.
The anti-aliasing needs a little more tweaking. I noticed some jaggies on my 51" HD rear projection set.
Overall though, this demo kicks ass and really makes me want the full game.
:tup::tup::tup::tup: