Yeah. I had the same reaction/questions too. However, the C6 ZO6 carried on for, what, 3(?) years before the C6 ZR1 came out in 2009? Could be a C7 ZR1 is on the drawing boards - waiting in part to see what wrinkles might need addressing in the C7 Z before going into production.
Time will tell, I recon. But, really...If Chevrolet were really serious about building a world beater again, would a front engine, push-rod car be the answer??