i remember that image from the E3 conference as it was announced.

39 minutes and 31 seconds.

I took the image from the OP and the image Pokoko posted from xbox.com. I moved the xbox one s from the OP image to be central like the xbox.com image and then overlayed it... the difference is pretty substantial.

Its probably because its actually about 40% smaller in volume, than the Xbox One.
The "PR" guys that did the image, probably just assumed it was 40% smaller in size (length, height).

But yeah its abit misleading that picture.

To sell you more stuff, its just a PR move.

The problem is MS already has so much weird PR communication stuff, like the mixed messaging ect.

They really dont need to come off looking untrustworthy or misleading, they do that far too often already.

It's actually 20% larger than the PS4 based on the quoted 40% smaller volume for XB1 and the external dimensions of the XB1 and PS4 (which from a volume perspective is actually more in the PS4's favour due to its trapezoidal shape). 

This might be a little easier, by moving the box down maintaing scale and taking the top off to have the same perspective we can see the difference between the actual size of the original XBO and how big the original XBO is in the advertising.

Hmm. Very Misleading but looks better than my huge cinderblock xbone. Think about the ps4 with just an external psu. Tiny

The best part is that misleading image is ripped straight from the Xbone S announcement video! It looks like they either took 40% each dimension or switched it and made it 40% the volume of the Xbone rather than 40% less volume. Either way, crappy move.

I lol'd. Hard... 

My guess s that they include the Power brick in the size for the XBox one.