February NPD - The Lost and Damned "would have outsold Killzone 2" at retail
While we still don't know exactly how many copies of GTA: The Lost and Damned were downloaded last month, Microsoft's Aaron Greenberg said last night that the figure was more than that achieved by Killzone 2 at retail - 323,000.
The exec told Gamasutra the DLC was "the most successful game add-on content we've ever launched," adding, "If that content was sold at retail, it would be one of the best-sellers across all platforms. It would have outsold Killzone 2".
It's worth noting that TLAD launched on February 17, while Killzone 2 released on February 27.