(Click on image to open original source site.)It certainly could be fake, but it's a pretty good one if so. A bunch of the "fake arguments" posted to the site linked above don't hold up on close inspection of the image. Eg:
1. Opaque sticker argument - No, it's not opaque. Calibrate your monitor and look at it up close in Photoshop. You can clearly see the red, cyan, and black bars through the sticker.
2. Model number != OSX Server system. Server model numbers are "M8..." that model number is clearly "MB...". Since the current iPods are "MA..." this would stand to reason for a new generation.
3. Non-centered dock plug - No, the hand-drawn label (which says "this side up" btw) is not centered, the plug is. If you zoom in you can see the edges of the white plug underneath of the cardboard label.
4. Photoshop tag in JPG image. - Yeah, because they photoshoped out something in the lower-right cornet of the image (probably a serial number that could be used to ID how the photo leaked).
5. Lamp cord. This one's debatable, but to me it looks like a "split" white cord (that breaks into two pieces) when you zoom in, not a lamp cord. The lower "half" of the cord appears to be slightly pushed overtop of the top half in the picture.
Either way,
I guess we'll find out on the 28th.