I've been thinking about this...
Ford HAD the GT... Dodge HAD the Viper, both great world class vehicles. Now Chevy still has a high performance vehicle, the Corvette. Now I know we heard that Chevy wasn't worried about the Camaro out-powering the Corvette, but seriously... if we got a $40k+ 500+ HP uber Camaro that would eat into Corvette sales. With an underrated powerplant in the SS it's not an issue, but for most people who goto a Chevy lot looking for power who see 550 hp AND a back seat for 42k and 430 hp w/ no backseat for the same price, they're going with the Camaro With the Corvette being a consisent sales performer throughout it's history I seriously doubt that Chevy is willing to introduce competition to it where there otherwise is none. Ford needs a HI-PO vehicle, Dodge needs a HI-PO vehicle, Chevy already has one that in most cases outperforms theirs for the same price (lower if you count markups). NOOOOw, I do believe there should be a Z/28 (yeah, writtn like that), but it should be a limited edition in the same vein of a GTR-Z or DB9 R that gets pretty much equivalent power as the SS, but strips the hell out of it to provide better handling and weight/power ratio. But the 500+ hp super car we were expecting, it doesn't make sense in the big picture, and in the mean time those that really really want to can strip the SS all they want and have their own homemade Z/28.
I could definitely be wrong on all of the above, but that's just the way I see it.