Now that the NPD has decreed our mere mortal minds are unfit to
handle hardware sales figures, we're tasked with finding
information from alternative sources -- wait, what's this? Aaron
Greenberg just tweeted that the Xbox 360 bested the competition
for the fourth month in a row? Search: complete.  Consider it
the Halo: Reach bump. Previously, the Xbox 360 enjoyed three
months of strong sales thanks to a hardware refresh, but
Bungie's 343 Industries' franchise has been known to move
consoles, so it's no surprise Microsoft dominated September.
Greenberg elaborated in his following tweet that Microsoft sold
483,989 hardware units in September, "a 37% increase over last
year." He also claimed the console is the only system with
higher sales year-over-year Source- Joystiq