I've just recently imigrated from NFS: Most Wanted, Carbon, and Undercover to the legal side of racing and I must admit that I wasn't quite used to it at first. Everything was a definite step-up, because:
1) Damage System can be very devastating, one wrong move and you would lose the entire race, and I tend to agree with the developers on this one. Sometimes, I even enjoy watching my Viper can pummeled as it hits the wall, only to realize that I'm gonna pay for it later...
2) Control System is very very different from the NFS series, and to be truthful, I'm already falling in love with GRID's. In NFS, the steering is smoothen and only at times jerky and the drifting was easy to adapt to, whereas in GRID, drifting isn't as easy as 'gear-down, hand-brake, steer, and throttle', it took me around three races to get used to the system, and it is very easy to learn (give or take a few destructive runs). Just because there isn't a stretch of highway to bust 300 MPH, doesn't mean it sucks. The highest I got was 259 MPH with Audi R10 TDI (its probably the best Le Mans car).
3) The graphics were superb, even on a low-end machine like mine, for a 2007 game, it exceeded its predecessors and played in the big leagues with the consoles. The only ones I find comparible would be the upcoming NFS: Shift, Colin McRae: DiRT, and Burnout Paradise (I know there are more).
4) Pricing in North America is totally overpriced. If it were around $39.99 CAD or $35.70 USD, then I would still think about it. Like others have mentioned (and have done, admit it), torrenting is the better solution.
5) General Fun Factor, probably one of the few games that actually kept me up all night (this was without trainer), and it kept me from playing FEAR 2 and CoD4, which is rare. I agree with the scores given by professional sites and reviewers (ranging from 8.0/10 to 9.5/10), this game is fun, but just overpriced. Looking forward to seeing the upcoming content pack and hoping for a sequel (preferably with more content and more customizing).