The changes that have hit NASCAR's Winston Cup Series have been widespread and their effect is being felt more and more, and the effect of these changes has shown no indication of being good for the sport; on the contrary, changes have had the effect of beginning an erosion of popularity of the sport.
The most dramatic changes in the sport of recent have been the implementation of a playoff format, the Chase For The Championship, for the season's final ten races, and the phase-in of a radical new car design, the Car Of Tomorrow, during the 2007 season with full implementation scheduled for 2008. Neither of these changes have had a positive effect on the sport, as fan disapproval of these changes has been widespread with no evidence of any increased fan interest in the sport with these changes.
The Chase playoff format isolates the top twelve drivers in points for the final ten races of the season; they are reracked in points to over 5,000 points, a mark mathematically impossible for any driver outside of the top twelve in points to break. The top twelve in points thus have only to race each other over the final twelve races; there is literally no incentive to actually win the race, as long as you beat the other Chase racers. While it is true that there have been few non-Chase racers that win Chase races - Tony Stewart in 2006 was almost the only non-Chaser who made any noise during that season's playoff run - this isolation of the top twelve from the rest of the field in points has done nothing but make the season's point race all the less relevent or interesting. By making the top twelve have to race the entire field, the old points format "kept them honest," if you will.
There is also the issue that on more than one occassion, a driver accumulated enough points over the final ten races to have taken a top-ten points finish under the old points format, notably Jamie McMurray in 2004. It doubly shows how the isolation of the top twelve in the Chase is only that - isolation, not exposure to competition.
There is no evidence that the Chase format has increased any interest in the sport; on the contrary, TV ratings and attendence for races has slipped noticably over the last four years, with some recent ratings barely exceeding a 3.5 rank. Some in NASCAR, notably Brian France, blame this on lack of promotion by former broadcast partner NBC, but this is patently absurd given the impossibility of avoiding promotion of NASCAR on any television or radio outlet.
Then there is the Car Of Tomorrow, an ungainly design built ostensibly for improved safety. The COT differs from the old model car this way - the roof is higher and more top-heavy; the nose is shorter; the front airdam has a huge gap, several inches deep, with a thin splitter on the bottom; the tail is longer and uses a wing instead of rear spoiler blade. The design was first tested on-track at Atlanta in late 2005, using a spoiler instead of the wing, and several models were tested to determine how the car would run in traffic. The result of the test was discouaging to an extreme - the car proved unable to suck up on other cars in the vacuum of air generated by a car at speed, and was unbalanced, to where very large rear spoilers were used to balance out the car.
NASCAR then decided to try a wing instead of spoiler, theorizing that the wing would not displace as much air and thus the nose of a trailing car would not lift off the ground in dirty air. This theory went down the drain as more tests were conducted in 2006 and nowhere did the COT show any ability to race in dirty air; aeropush was increased dramatically.
Drivers such as Jeff Gordon and Jimmie Johnson proclaimed on more than one occasion during testing that the COT was useless in dirty air. NASCAR officials, however, kept insisting the COT would be competitive and would lower costs because theoretically the design, limiting aerodynamic customization to a preposterous extreme, would allow teams to resue a single car at multiple tracks - a claim that ignored the long-standing team practice of building multiple models of racecar, with some chassis used on varied tracks and the remainder of a team's fleet built as backups for inevitable racing attrition.
NASCAR debuted the COT on short tracks in 2007 and the results were as knowledgable observors expected - inferior ability to race, a reduction in passing, especially in the top fifteen of a race, and no evidence of any reduction in costs. "I could have told you from when I first drove this thing that the aeropush would be worse," Jeff Gordon pointedly noted in July 2007.
Fan dislike of the COT has been expressed at every conceivable forum for racing, and the ratings and attendence have begun to bear this dislike out. NASCAR, for now, is pressing ahead with the COT, but it seems absurd to think that, as ratings and attendence continue to erode, NASCAR won't at some point realize that major mistakes have been made with these changes.