Started when Garage419 did the GT-R vs ZR1, and now the fight continues between the ACR and ZR1. Andi Bartichi put this video together to show the two side by side. Looks to me like the Viper is a little more composed, but then it should be with all that downforce and rubber.
Ferrari is stepping up to support the new A1GP Racing series with engines and chassis development. This is a nice introductory video to the testing that is being done at Imola in preperation for the next season.