I've got mixed feelings about it. The tunnel scenes were unnecessary and if they were out to make a movie about "drivers" -aka people and cars which can go around turns too - they kinda failed. The more sideways you go around a turn, the slower you are - I know it looks better on camera, but c'mon now.
I thought the cars were good in it and its obvious they put a lot of time and effort into actually getting stuff correct in this movie compared to others. I also liked how they tied this movie in with the first one so tightly. I think this was more of a sequel to the first one rather than the others were.
The slow parts lasted a little too long, in my opinion, but as a story, the movie was really good.
On a side note, I laughed really hard in the "main" race sequence when Paul Walker yelled "SHUT UP" at the GPS, much like the scene in my avitar. Too bad he didn't get another "Danger to Manifold" light...
Good movie - I'll probably be seeing it again with a different group of people this week.