I had the same line of thinking as SilasX. Conceptually, the change is that instead of deferring work to the last moment available, it is now done immediately. This is the very difference between lazy and eager computation. As I'm not a Haskeller, I didn't immediately realize the strong connotation with language features. Sorry for the confusion.
Unless I am mistaken, they didn't change the template language evaluation strategy from call-by-name to call-by-value.
They did change the implementation from an interpreter to a compiler, though.