I would like to add my experience. On December 22, 2013 I purchased a 32 GB iPad Air, paying a little over $600.00 after tax. I left it in the box and gave it to my 11 1/2 year old son as a Christmas present. He was taking impeccable care of the unit. Every time I turned around, he was cleaning it/ wiping off fingerprints with a damp microfiber cloth. We have the Logitech keyboard/case also sold at Apple stores. The iPad Air hadn't left the home. It hasn't been dropped. My son watches Netflix on it a bedtime. He left it on the bed Sunday and went back to school Monday. On Monday January 6, 2014 after school/work, we noticed a hairline crack on the unit, similar to XVortex's posted image on this string. We have taken photos of the crack including the sides of the unit to demonstrate, if need be, there was no drop or impact. The side borders and back of the unit are impeccably clean. Aside from the hairline crack, the screen is clean. My son was obsessing on over the care he is taking of the iPad air. My Wife has an iPad 2. My son was striving to keep hi iPad Air in impeccable shape. My Wife's has no screen damage.
Meanwhile back to the story. Because my kid was upset, I went to the local Apple store on Monday evening January 6, 2013 to make a Geniusbar appointment--after reviewing the posts here. I was polite and courteous. Before I had the appointment set, I was toled a tech could look at it quickly, but he was with another customer. I was told accidental damge isn't covered and was told that for $279.00 they would swap out my 15 days purchased/12 days out of the box $600.00 ipad.
I am happy to have one of my older children upload the photos of the hair line screen crack and pristine unblemished sides of the iPad air. I own Apple stock and have faith in their product and service. The product must be designed to be suited for its intended purpose. Normal, non negligent use should not result in damage. I understand the product is designed with thinner glass to reduce weight. However, there needs to be some durability to allow for normal use. I know the unit wasn't dropped there was no accidental bumping, packing in a back pack or anything else. De care was used, but it still cracked.