Gray 360 appears in Microsoft E3 rehearsal photos

We don't know exactly what this means ... heck, we don't know what it means at all, but we thought it was too cool to not pass along to you. Eagle-eyed (and quick screen-grabbing) reader Rickard Gudbrand sent us a screen capture he took while looking through Gamerscore Blog's flickr photos of Microsoft's E3 rehearsal. The image shows the three Xbox 360 SKUs we all know and love, in addition to a mysterious fourth wheel that appears to be a gray 360. Making the whole thing even weirder, after Gudbrand commented on the photos' four boxes, the pic (and others showing the stage) appear to have been removed.

So ... what is it? As you can see in the image, the box seems to be on the opposite end of the spectrum from the Elite, which maybe indicates that it's at the opposite end of the pricing spectrum too. We heard about some new, cheaper production methods for the 360, could this be a low-priced model taking advantage of that? We'll hopefully find out tonight.

[Update: There's at least one image (right here) on GSB's flickr site that's showing four 360 models. But when zoomed in, the far left console appears to be white. So, is it gray or white? And what is it? We just don't know. Thanks for the heads up, Cyrus.]