Warner Bros. Interactive Entertainment and DC Entertainment announced that Batman: Arkham City has shipped 4.6 million copies worldwide in the past week. That's double the amount sold for Asylum in its first seven days.

"Shipped" doesn't necessarily mean "sold." Still, it shows that the demand for the game is huge. These figures put Arkham City in a position to be one of the top-sellers this year, too.

Sales should continue to be strong throughout the fall thanks to solid reviews. Currently Arkham City has a Metacritic score of 96 and 95 for the PS3 and Xbox 360 versions, respectively. This makes Arkham the highest-rated game on both platforms thus far in 2011.

"Batman: Arkham City is one of the best action adventure games, proven by the tremendous reviews, and it further establishes the Batman brand as a marquee franchise for our growing business," said Martin Tremblay, president of Warner Bros. Interactive Entertainment. "Rocksteady Studios went above and beyond in delivering an incredible game and the support of the entire team at Warner Bros. Interactive Entertainment and DC Entertainment drove the excellent campaign a game like this deserves."

In Arkham City, all of Gotham's most dangerous prisoners have been relocated to a walled-off section of the city. It quickly becomes apparent that this experimental prison hasn't made the city any safer, though. Batman must head into the chaotic "Arkham City" and do battle with the Joker, Mr. Freeze, the Penguin and a host of other super-villains.

If you're still considering whether to pick up the game, read our review.