I had this happen to my Pre back in June/July. 3 weeks into owning the phone it had a split at the USB cover that made its way to the screen. I took it to Sprint and as soon as they saw it they said 'physical damage' and wouldn't touch it. I called Sprint CS and they told me the same thing. Well after much complaining about it I was able to get a 50 dollar credit on my bill to offset the 100 dollar charge through the insurance. I told them it was beyond cosmetic but they didn't care. The phone itself was never dropped or damaged, and was in flawless condition... besides the crack. No signs of physical abuse.

Long story short, it IS a problem with build quality since the USB port pulls on the housing when you try to remove it, but since there is no recall of the phone for this defect, you WILL have to pay 100 dollars to get it replaced though insurance (if you are paying the 7 dollars a month for TEP).