Each driver gets his own set of attributes that will dictate how well he handles certain aspects of a race. While some dudes may not have the chops to hang with the big kids, you can build their skills up so they can tackle even the toughest racers. The most exciting thing about this skill-building system is that it happens dynamically during the race, so if you start out with a busted chump, clean racing will cause his racing prowess to grow, giving you better handling and speedier acceleration. If, however, you like to trade paint and do most of it with the wall, you'll lose those precious skill points and find your car difficult to handle.
As incentive for selecting a rookie racer with low-level skills, there's a wagering system that enables you to play the odds. You can bet skill points that your fresh-faced challenger can win a race that he doesn't stand a chance in and get rewarded with a large payoff of skill points if you take first. Of course, just as your skills dynamically increase and decrease, the computer-controlled racers will ramp up in ability if you find yourself leading the pack.
You won't have to wait too terribly long to tear up the track as NASCAR should collide with store shelves in early September, so you'd best start sewing patches onto your jacket now.