One of the aspects that has made the iPod so successful is the fact that you can access all of its functions through the click-wheel with one hand. There's no way you could do the same with an "iPod Wide"; it would completely kill the usability of the thing.
EDIT: Now that I take a second look, I see the body isn't any wider. Not only would this probably be impossible, but it doesn't offer much of a wide aspect ratio. Taking a look at my ipod, it would probably only gain about a half or quarter inch on each side. This doesn't even make sense. In fact you can even tell in the image with the "iPod wide" showing the thumbnail pictures. The regular iPod on the right displays 5x5 thumbnails while the "wide" is 5x7. Thats nowhere close to wide, just ugly.