This "Glassgate" story got rolling with a report in the gdgt newsletter by Ryan Block, http://gdgt.com/discuss/with-antennagate-over-is-glassgate-next-iphone-ani/#1yf7 who says he spoke with sources inside and outside of Apple about this issue, but was unable to get an official Apple comment.
Block writes: “Apple has apparently found that non-bumper style cases — specifically those that slide onto the iPhone 4, which are occasionally prone to particulate matter getting caught between the rear of the phone and the case — can cause unexpected scratching that could quickly develop into full-on cracking or even much larger fracturing of the entire rear pane of glass. To put it another way: Apple is afraid you might buy a standard slide-on iPhone case, put it on your phone, and then discover the next time you take it off that the entire back of your device has been shattered by no fault of your own.”
Apple is said to be taking it seriously, looking to avoid the sort of backlash it got when reports surfaced over the summer that the iPhone 4’s antennas didn’t work correctly http://www.networkworld.com/news/2010/071910-the-iphone-4-antenna-gate.html when users gripped the phones in a certain (and quite natural) way."
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