On the whole, it is an interesting, but not a terribly successful way of splitting things up. The genius of a race like the Cannonball Run is the pressure of having to keep going for an extended period of time. While you can't ask a gamer to sit there for several days and play nonstop (even if some of us do), here the races regularly feel too small. With levels being just a few minutes long, while your character's nerves may grow raw and he may seem more frazzled, the player doesn't feel that at all, and some of that emotion ought to come across.
Beyond that, while there sometimes is the sense that you're actually going from place to place, more regularly it feels as though the game has just kind of fastforwarded the race a little bit in order to drop you somewhere new so you can do something different. In short, it's a cross country race without much continuity.
But, when looked at separately, each of the individual levels are spectacularly fun. In terms of said levels, The Run is well paced and well laid out so that things are constantly being mixed up and changed. The XP you earn, too, feels well orchestrated – points are given for different kinds of passing (be they clean passes, dirty passes, many people passed at once), and you're constantly unlocking new and better things.
Then, there's the actual racing. This is, most definitely, an arcade style racer, and it remains one even if you ignore the resets you're allowed mid-race when you crash your ride (and you will crash your ride). Cars make turns which shouldn't be possible, fail to make turns which ought to be easy, and take way more damage than any car possibly could before they actually get wrecked. You also auto-regenerate your nitrous boosts which probably isn't the sort of thing you see in any car save KITT.
The Run features a pretty sizable list of cars (and more if you buy the limited edition version of the game... not that you get KITT with that). You'll get the chance to race everything from an Aston Martin V12 Vantage to different Dodge Challengers to a Ford Police Interceptor Concept to a Toyota Supra, and even a couple of different Paganis. Cars fall into three main headings: exotic, sport, and muscle, and do act somewhat differently, but not hugely. You will find that certain cars work better on certain courses, but you ought to be able to get by the courses on most difficulty levels in any of the vehicles.