looks like it is for real...
http://www.chevrolet.com/camaro/
new corvette engine specs too. Looks like gas mileage is not a concern here these days:
"A stunning new benchmark in Corvette performance
With its 638 horsepower LS9 supercharged V8, ZR1 is capable of 205 mph on the test track
6.2 Liter V8 with Eaton TVS Supercharger and intercooler produces 604 lb.-ft of torque
Massive Brembo Carbon Ceramic Brakes "