Considering that mass production and consumption has grown exponentially during the past 11 years, plus the fact that Apple's prices have been forced to become competitive with PeeCs, the quality of Apple's products remains quite high, by any standard.
This ATI graphics card problem affected greater or less than 12% of new iMac owners, and was due to a component not manufactured or overseen production wise by Apple. Coming up with a fix required first identifying specifically which batch of ATI cards had interface/memory problems, and then rewriting code for that specific firmware/memory address glitch. In the interim, Apple gladly swapped iMacs for new ones - this is where quality assurance counts the most, well above quality control. When a problem surfaces, will the company address it, remediate it until a solution is found, and then produce a solution? Regarding this case, 3 months is not an unreasonable time to produce a fix for this problem.
As far as pixels are concerned, I own more than 2 dozen Apple LCDs in the form of iMacs and/or 23"-30" monitors - never had a bad pixel. Apple does stand by their hardware, as well as components manufactured by other vendors, and will replace whatever it is to your satisfaction. This has not been my experience with Dell.
