EDIT: Refer to post 5. Possible game breaking malfunction. Avoid game until resolved.
I got this yesterday and have been playing it for a day now, and it's the real deal. Finally a realistic racing sim on a Nintendo system, and it's good. It's basically been ignored by the gaming media and there's no impressions anywhere so feel free to ask me a question about it.
First off, the graphics are pretty crap, the tracks and cars are highly detailed but there's a massive blur type filter all around everything, and some random glitches, plus a crap draw distance with things popping up out of nowhere in the background at some tracks. Doesn't even look that good for a PS2 game. It has "moments" where it looks good but it's far too inconsistent, and some tracks look better than others. All the tracks (GREAT track selection by the way) are remarkably detailed though, and seem accurate to 100%. Also the "weather effects" are absolutely pathetic (back of the box says they are "incredible", yeah incredibly lazy), rain looks awful and barely slows you down at all, plus you still take the exact same racing line so it's basically like the same track with slightly less grip.
Secondly the handling is the most realistic in a game i've ever played, even better than Gran Turismo. First thing I did when I got it was turn off all assists and I was battling the car big time, under braking, acceleration everywhere on the track, it also allows for heaps of customisation. There's 6 different levels of "assist" for multiple categories (basically braking, accelerating stability), and the option to turn on an ideal racing line to show you the fastest way around the track. The great thing about that is that it's real time, not just some coat of paint on the road, it will adjust braking zones to your current speed. This would be a great game to show casual or non-fans of the genre how to drive properly and maintain speed. Also for the hardcore you can adjust things from ride height to spring stiffness. Beats GT Pro Series custom horns. Also there's real time splits to the car in front and behind you, that is constantly changing to the nearest hundredth, and it's a good way to find out where you are gaining or losing time to rivals.
A huge negative is not only is there no WiFi, but no multiplayer at all. PS3 version has an amazing online mode and I don't see any reason at all it couldn't be done on Wii. The AI is incredible awesome, aggressive and smart, but doesn't nearly make up for this.
Controls are good with the nunchuck but the Wii Wheel controls leave a bit to be desired. It's not as good as Mario Kart or even GT Pro Series usage of it. The big flaw is that once you've turned it 90 degrees, it'll stop registering and think you're going straight, and since there's nothing to "lock" it into there, it's ridiculous to expect us to turn exactly 90 degrees for a full turn, mashing right or left on the nunchuck analog is a better alternative. Plus with the nunchuck controls you can wave the remote around to shake the drivers fist in cockpit view.
Anyway i've only played a day and still have heaps of stuff to unlock (there's heaps of stats and achievements) so i'll leave it at that for now. Overall it's a great game but incredibly obvious the Wii version wasn't the main focus. If someone made an exclusive racer for Wii making use of its strengths it would be amazing.
Oh yeah another thing this is the first Wii game i've played that requires you to detach any GC controllers. "unsupported extension detected, please disconnect" popped up when I first started the game.