I went to the Apple web site and made an appointment - my local Apple store in Tysons, VA is usually quite busy all the time. I brought it in at noon EST today and, as usual, the place was packed. The Mac Genius I spoke to (Rob) was about as friendly and knowledgeable as you get. He asked a few questions about the MacBook and when I explained to him that I just did a Time Machine backup right before coming in he high-fived me for using Time Machine. Just a real upbeat guy - it was a good customer experience and it was nice to see someone that clearly loved what he does.
When I asked him why this was happening he said that the magnets they use in the lid to keep it closed were too strong and that they created too much pressure on the edge of the case, causing the cracking. He said they would need to replace the top-cover, that they had them in stock and fortunately they would be able to get it down within an hour.
I headed off to my lunch appointment and about an hour in the Apple store called to tell me the machine was ready. I inspected the machine - there was a new top plate replacing the cracked one. It seemed to have a slightly different texture than mine.
When I asked if this could happen again the person at the counter went back to talk to the technicians and returned to tell me that the new palm rests were made of a different material that should eliminate that from happening again. If you look at the before and after pictures above you will note that the repaired version sits a little more flush than the previous one.
Not wanting to leave this to chance I went on Amazon and ordered a Macally Protection Shell for my MacBook based on the recommendation I received here. It should arrive in a couple of days.
Though my MacBook is under the care of a three year warranty the hassle of driving all the way to the Apple store (especially at $4+ per gallon) is not something I look forward to.
The nice experience I received at the Apple store has helped assuage the frustration I felt when my new machine started cracking, though I'm still a bit disappointed. I've had several friends tell me that they have the same problem on their MacBooks but they are out of warranty so they are out of luck. I personally think that since this is a design defect—not an abuse issue—that Apple should repair these even if they are out of warranty.
I do find myself holding Apple to a slightly higher standard than I would say HP or Microsoft. Part of this is because I am getting everything from one vendor; no finger pointing that it's the fault of the OS, a driver or the hardware vendor. But the main reason I take Apple to task is that I do believe that Macs are outstanding devices.
The few problems I've had stand out in glaring contrast to what otherwise has been an outstanding experience.