Here's my little review after playing it yesterday.
In terms of gameplay it's good enough, no real complaints about physics.
most annoyances come from the menu systems though.
I mean, you win a car and instead of just appearing in your garage with a popup saying "You've won such and such car", it takes 2 minutes to go through a stupid 'ceremony' where the car drives 10ft towards you. I mean what????
And until you do this you can't use the car you've just won.
Apart from that, it's a shame many cars don't have interior views but hey. For £32.99 which is what I paid from Blockbuster I can't complain, well worth a purchase.
Licenses are fun, find myself managing to get 75% silver and about 25% gold which considering it's the first time I've played this in months (played GT5P) it's pretty neat
As for online, no experience so no comment.
*Currently has the silly Black Galanza turbo thing and about 90k in credits. WOOT*. /me knows it's not much.