The official NPD numbers are in for September, and the Xbox 360 swept, even beating out the Nintendo Wii for that month.
We think it has something to do with Halo 3.
Here are the hard Numbers, from industry analysts at the NPD Group:
Hardware
Xbox 360: 527,800
Wii: 501,000
Nintendo DS: 495,800
PlayStation Portable: 284,500
PlayStation 2: 215,000
Playstation 3: 119,400
Game Boy Advance: 75,000