On the topic of same looking cars and why.
From 2000
http://nascar.about.com/library/weekly/aa031400a.htm
From 2001
http://auto.howstuffworks.com/auto-racing/nascar/nascar-basics/nascar-car-of-tomorrow.htm/printable
Quoted from the link above.
Up next, we'll look at how the Car of Tomorrow is leveling the playing field for all teams competing in the NASCAR series -- regardless of whether they're sporting Toyota or Dodge decals.
Production and Standardization
Streeter Lecka/Getty Images
The Car of Tomorrow cockpit boasts a number of safety improvements over the old model.
With the inception of the Car of Tomorrow, the cars used by each of the different teams are much more standardized across the board, making NASCAR more like spec racing than ever before. Spec racing is a form of competition where drivers compete in nearly identical vehicles. When every car on the track is prepared in the same way, the race becomes more about driver skill than engineering and who has the most money to build the best race car.
The Car of Tomorrow can also be seen as a cost-saving measure for the competing teams. In previous years, NASCAR teams had to build several different cars for the various tracks on the NASCAR circuit. They built different cars for short tracks, road courses and super-speedways. The Car of Tomorrow uses the same frame, roll cage and body for all different types of race tracks. Of course, most teams do have more than one car; mainly because there's always a chance that the driver may destroy one during practice or qualifying.
But critics argue that building the new car was a multimillion-dollar investment for racing teams -- as they had to discard all of their old cars in favor of the new design -- and they won't actually benefit from the reduction in costs for years to come.
At the same time, many fans contend that making the cars more or less the same takes away from NASCAR's "run what you brung" days where a variety of vehicles raced against each other. Many fans have said that they don't want to see a spec racing series, but instead want a race where there's a reason a Dodge can beat a Ford, or vice versa.
From 2006
http://www.racelinecentral.com/CarofTomorrow.htm
Quote from above link.
The new design of the Nextel Cup's "car of tomorrow," like this Dodge Avenger unveiled at the 2008 Detroit auto show, will eventually yield safer, more competitiveand less expensiveracing. (Photograph by Jim Dunne)
This season, astute race fans are noticing something different about champion Jimmie Johnsons Nextel Cup car. Aside from the paint, headlights, grille and number decals, his Chevy looks exactly the same as Matt Kenseths Ford, Juan Pablo Montoyas Dodgeeven Michael Waltrips Toyota. Its been a long time since Cup cars bore much of a physical or mechanical resemblance to their namesakes. However, up until this year, the race cars did look different from each other. A NASCAR Dodge didnt look a lot like the production model, but a fan could never mistake it for a Monte Carlo. Now, thats all changed.
Beginning with 16 races this year and expanding to 26 races in 08 and the full season in 09, NASCARs premier series is essentially a spec series. In other words, the cars are basically identical except for their enginesall built to the same exacting specifications. Its taken NASCAR five years to create the blueprint for the new racer, which it has dubbed the Car of Tomorrow. Its purpose is threefold: Increase safety, reduce costs and provide closer competitionwith racer protection topping the list. According to NASCAR communications director Kerry Tharp: From the very beginning of this project, the Car of Tomorrow has been all about improving driver safety. The new vehicle is, essentially, a big crash-survival cocoon.
From NASCAR.com 2006
The Car of Tomorrow is the culmination of a five-year design program being conducted at NASCAR's Research and Development Center in Concord, N.C. Of primary significance are safety innovations; performance and competition; and cost efficiency for teams.
I say that NASCAR has done what they think is correct and I applaud them for it.
I don't care which type of car wins I want to see competitive racing and NASCAR is the most competitive racing I watch.
I watch quite a few series too.
Sorry for the long post.