An FCC filing today by Mitsumi exposed what appears to be a Nintendo DS testing platform.  As you can see, the board above has all of the components of a Nintendo DS, including two screens, controller, and camera.  However, these components are installed on a spacious mother board, presumably to facilitate testing.

It’s unclear if this testing board is being used for a new version of the DS, or if Mitsumi is simply updating their existing WLAN card in the current iteration of the DS.  It’s also possible that this isn’t a testing board at all and Nintendo is just planning to release a ridiculously large version of the DS.  Either way, it’s an interesting look at the DS and the testing process Nintendo’s suppliers go through.