This Gizmodo article actually contains a believable vein of information -- as opposed to a lot of the crazy pronouncements on some threads (i.e. "Apple engineers are idiots," "Apple quality control sucks," "everyone's just
imagining the yellow tinge," "Microsoft spies are sowing seeds of discord in Apple forums," "Elvis and Marilyn are hoarding all the non-yellow screens for themselves," etc.)
Gizmodo's source hypothesizes that suboptimal packaging, rough handling, and/or environmental conditions during storage/transport may be causing subtle gradient issues that simply
don't exist when the assembled iMac is tested at the factory. (The basic defect may be a traumatic misalignment of the light diffusing layer behind the LCD panel.)
This hypothesis may be related to the obvious handling/packaging inadequacy that caused the "cracked glass" problem. It also might account for delayed understanding of the gradient problem. It also might account for the apparent problem with regional batches (e.g. some posters report multiple replacements shipping to their location with the same error; one indefatigable poster reports having gone all over his hometown seeing gradient issues on at least 20 different iMacs; other posters report that all the iMacs in their area "look just fine").
Most intriguing is the Gizmodo observation that "careful assembly and dis-assembly resulted in the yellowing disappearing."
Of course these interesting morsels are surrounded by the usual load of, um,
other stuff. But, hey, welcome to the Internet!
