Mystery high-performance GM engine: LS9?

Images of what appears to be a new high-performance engine from General Motors have surfaced on the web. Snapped by member 'norm' of the Digital Corvettes discussion forums, there is much debate over what these images depict. Some believe what we're seeing is the forthcoming LS9 Corvette engine for use in the "Blue Devil" or "Stingray" 'Vette. Others say's it's a truck engine, possible for a 650 horsepower Cadillac Escalade. While the Escalade-V argument is compelling, it's worth pointing out that a recent published report suggested Cadillac has no plans to create a V-Series Escalade or SRX, because it would be unnecessary and unsafe. Images of the engine after the jump...