One might assume that the graphic in the ad is simply an icon, containing only the bare-bone characteristics that make an iPod an iPod - white body, gray screen, headphones - because it doesn't seem to change with the times. This would explain why the gray wheel has never appeared. The iPod changes but the iCon remains the same. But when the 5th generation iPod was released with its well-endowed screen (clearly a selling point), lo and behold, that little gray box on the ads grew bigger, too. So why then is the gray click wheel still left out? Is it not a selling point, as well? If they are so proud of the click wheel as one of the "distinguishing features" of the iPod, why not include it in the advertising?
I have not been able to figure out why the click wheel turned grey. All other functional and aesthetic changes have been justifiable, even the fact that my not-so-outdated PowerBook cannot connect to the new iPods has some basis (because Apple has deleted firewire). I can't imagine Jonathan Ives would disagree that the simplicity of the all-white iPod has been compromised. Clearly the advertising agency knows what looks good and the grey wheel doesn't make the cut.
From a design perspective, I can't figure out why they made this change. It forces the circle of the click wheel to compete with the rectangular screen, creating an awkward relationship of simple forms. This was slightly addressed by making the wheel smaller on the 5th generation where we come to the future trend of the iPod: black. The black iPod is a reminder that this is a different time - my old PowerBook's subtly curving sides and glowing apple that is right-side up when it faces me, closed, and only upside-down when I can't see it because the computer is open. Maybe when the apple flipped so did the company. It became less about my personal connection with my computer and more about how I looked with it.
How does this relate to the iPod? The gray wheel is now avoidable but I now have to buy a black iPod with all-white accessories. Could this be why the headphones disappeared from the official iPod images seen in the lineup above? It seems inevitable that the next iPod will have to be essentially the iPhone, a product for which there is no white in sight but still comes with white headphones. The Clickwheel will be gone but the earbuds have taken its place.
As such an innovative company Apple seems to be scared of losing it's new found success and holds on to design icons when they make no aesthetic sense. No wonder it has been almost 5 years since a true redesign of the PowerBook, or MacbookPro as it is now called. They changed the name, the system and the processor but the design has remained constant. Apple designs have won many awards but seem to be in a holding pattern while their success keeps escalating. This method might work with some companies - such as Porsche, constantly refining a vision to a pure form - but Apple seems to be making poor design choices based on pop culture success and advertising iconography rather than looking hard at the actual product and refining it based solely on design.
To me, the gray wheel represents a tipping point into the dilution of Apple's design vision that just so happened to coincide with the success of the iPod. I will stick with my aging, titanium PowerBook and all-white iPod until further notice.