... Sure gas prices and the economy have a little to do with it, but for the buyers that would put forth the money to buy the Z28, gas prices mean little.
The main reason is that there simply is no need for a 550 HP Camaro. Chevy's greatest competitor is Ford, and their model lineup is stacked accordingly. Camaro V6 vs. Mustang V6, Camaro V8 vs Mustang V8, Camaro SS vs. Shelby GT500. Regardless of the power gap between the last two, they'll be nearly evenly matched.
So why the hell would you need a 550HP Camaro?! Just buy a 'Vette.
But yeah, I'm seeing this as a marketing gimmick. Axe the Z28, public outcry, bring it back...it's the way of supply and demand.