Joystiq got its hands on leaked documentation that suggests the Xbox 360 will support USB mass storage devices in the near future. Screenshots lifted from the documents reveal support for externally connected devices well over the 512MB capacity of Microsoft’s current Xbox 360 memory units which are presumably now on the road to obsolescence. A note within the document from a Microsoft software engineer also acknowledges the proliferation of high capacity, high speed USB storage devices and confirms that Microsoft will release an Xbox 360 system update in 2010 to provide support for this inexpensive class of external storage. This added feature is good news for those XBOX 360 owners whose core system has limited or no on-board storage as they will be able to add up to two 16GB USB flash drives and use them in lieu of the pricey Microsoft add-on hard drive. With the ability to cheaply add on 32GB of storage, that Xbox 360 Arcade and its sub $200 price tag looks a bit more attractive, no?