MacBook Air 13" Command Key Backlight

I recently purchased a Mid-2011 13" MacBook Air. I "love it", but it has a curious anomaly with the backlight behind the left Command Key. The right Command Key shows three little backlight segments underneath as you tilt the keyboard up and look under it. The left Command Key only lights two segments leaving the center "mm" looking dim because there is no light underneath the key in the middle. At first, I thought I simply had a defective keyboard and I went to Genius Bars at two local Apple stores and called the customer support phone line. The nice fellow at the first store told me that the problem occurs on all 13" Airs, but not on the 11" models, and sending the unit out for repair would only end with the same problem. Curious? I brought my Air home and called the Customer Service number. He consulted with his Senior Advisor and told me that I had a defective keyboard and should take it into an Apple store for service. I went to a second Apple store and they replaced my original Air with a brand new one (great service), but only to find in the store that the replacement Air has the same problem. So, the first Genius Guy was right, but what a curious little problem!! Why would not both Command Keys be lit evenly, with the problem or defect apparently only occuring on 13" models? Any ideas or solutions?