Yes because its so very likely that they had access to the beta before anyone else to make that video but couldn't patch it before gateway themselves released it.... very logical....
Like I say. I didn't see the video so I don't know how genuine it may or may not have been, but I don't see how it could have been very hard to fake. Why would they need access to a beta to make a video of a 3DS playing, what game was it? Zelda?