The Dark Knight returns in a blaze of fury, taking on a whole new generation of criminals and matching their level of violence. He is soon joined by this generation's Robin — a girl named Carrie Kelley, who proves to be just as invaluable as her predecessors,
So is this story canon with the whole series? No, this was it's own contained universe designated Earth-31. It may not exist anymore with the New 52, but most likely does. The only stories known to take place in this universe is The Dark Knight Strikes Again, a sequel to The Dark Knight Returns, and All Star Batman and Robin. Sort of weird given old Batman lived in the 80's while young Batman lives in 2008. Whatevs.
I only wish the art made more of an effort to reflect the time period. Based on the DKR timeline, it's assumed that the Last Crusade takes place at some point in the early to mid-1970's. But much like The Dark Knight III: The Master Race, this issue settles merely for replicating the look and feel of the original mini-series rather than trying to convey the passage of time in Gotham. Apart from the depiction of Bruce Wayne himself, there's no indication that a decade or more of time separates The Last Crusade from The Dark Knight Returns. Whether it's the fashion, the technology or the depiction of the eponymous talking media heads in Gotham, nothing about this comic screams "Gotham in the '70s."