Update: this post was based on a IM talk with Pedro, and I understood that the entire cable was 20cm. Apparently is 20cm over the length of an Apple Keyboard. And in that case, I really don’t see any problem with it. I do not agree, however, that an extension cable is a solution for this. I don’t care how much it costs. It’s just not “right”.
Anyway, let me clarify that he is talking about the Mighty Mouse USB cable. He has some valid points: 20cm is not enough if you plan to connect the mouse to a desktop computer. And I didn’t find any mention of the cord length at the Apple site.
Yet, I think that if you have a Apple laptop, 20cm seems just right, just enough cable not to get your hand tangled with excess cable. On the other hand, some people (like me) use the laptop as a desktop replacement, and it sits high in the air, on top of a Griffin Technology iCurve.
I think the idea behind the 20cm cable is that you are supposed to connect your mouse to the USB port on your wired Apple keyboard. Of course, if you have a bluetooth keyboard, you’re out of luck, but then Apple expects you to fork some euro more for the BT version of the Might Be Here Some Day Now Mouse.