I was one of those that fell for the pre-game hype and really looked forward to it. I have the t-shirt to prove it (literally, since I bought the special edition box).
The few hours of the game I had so much fun, the game looked awesome, and I could feel the immersion. However, after driving through the umpteenth guard post and have everyone and their mother shooting at me as soon as they saw a car coming down the road (a post earlier in this thread sums this up perfectly) I stopped and thought "wow, this is pretty boring". The missions are all of the same kind, and I cannot believe this game goes for the innovation title.
Yes, it uses DirectX 10 and it looks amazing, but they didn't even bother to code in a faction system! Even Boiling Point: Road to Hell managed to do that, and they pretty much messed up everything else!
In short, I think if I had written a review after my first 5 - 6 hours, I would have given the game a very good score. If, on the other hand, I would write one now, it would look a lot less impressive.