I love Apple's customer service, it's seriously the best service you will receive from a company.
I recently went to my local Apple Store to get my earphones replaced as they were a bit worn out from daily usage. He told me that my iPhone was out of warranty as it was a 3GS, but luckily it was covered with Apple Care and as soon as I mentioned it, he rushed over to the product stand and got me a pair of brand new earphones. Didn't even check the serial number of my phone.
In addition to this, I had some problems with my headphone jack of my phone, as it did not work with some high-quality generic branded earphones. He took my phone to the back and came back later, saying that he fixed the problem and even painted back the headphone jack rim, which was a little bit chipped.
I was a bit skeptical at first, however once I tested my phone the headphone jack worked as if the phone was new!
I have also heard stories of people admitting to accidentally breaking their iPhones and having them replaced, free of charge, by a Genius.
As Steve Jobs says it; 'we love our users...when we succeed, they reward us by staying our users'.