Gaming website Joystiq reports that an upcoming firmware update will give Xbox 360s USB mass-storage support.

Joystiq claims it obtained documentation that revealed the upcoming feature, which it says has since been verified by two other sources (although Joystiq fails to name the sources in its coverage).

Reportedly, the document was written by a senior development software engineer at Microsoft, with an “increased market penetration of high-capacity, high throughput USB mass storage devices “ being the reason for the feature's implementation.

The feature will allow users to store Xbox Live Arcade, Games on Demand and even full disc-based Xbox 360 titles on an external USB drive. In the case of disc-based Xbox 360 titles, the games will still require the disc for verification purposes (much like an official Xbox 360 hard-drive install does now).

Previously, only official Xbox 360 memory units and hard drives could be used for game storage.