This looks fake... how can a simple connector melt?? The battery melting is a possiblity, but a connector that isn't linked to the laptop.... I smell rotten fish.

I also dont buy the story of a "simple" failure. One look at the other pictures, particularly of the MacBook side, shows the bright gold plated pins which would have been destroyed by the melting connector. I am leaning more towards a thermal event caused by water intrusion. The orange rusty spots on the cable's strain relief as well as the rather banged up (for a few day old machine) exterior of the MacBook seems to point at a failure due to abuse rather than a non-provoked failure.

Okay guy's calm down and begin to look at this event rationally. What does the appearance of that cable tell you. First, that the connector's end was were the heat was generated. That is why the END of the cable shows thermal damage and NOT the cable. What could cause this? Well, bridging the terminals with a low resistance conductor (direct short) could most definitely cause this. So, one possibility is that the cable was yanked out (As the owner stated) and came to rest in a position where a conductive object bridged the pins. But, if this was the case, there would be no damage to the laptop's port. The damage would be to the connector, and conductive object only. So, we can pretty much rule out a direct short of the cable. Now, what about the idea of a liquid related short? Well, current only passes well through aqueous liquids at fairly high voltage levels. The laptop power brick's 15.5 or so volts would not push sufficient CURRENT through any water based liquid to overload that connector. Don't believe me? Take a glass of water, and pour it across the top of your cars 12.6V (14.5V if you do this while your car is running) battery. Observe, no dramatic shorting occurs! (Even though your car's battery can flow nearly 1000-amps of current.) Why? Insufficient voltage! So, in this case, I'd feel pretty damn certain that we can rule out misplaced feline urination as a possible culprit of the excessive current damage we see on this connector. But what about the "yellow" plastic you may ask. Well, I'd be willing to guess that white plastic turns colors as it is heated beyond it's normal operating temperature range. Don't believe me? Put some plastic in the oven and tell me what what happens when it gets to about 350 degrees or so. So, the 50-thousand dollar question is: What could cause excessive current to flow through the connector while it was plugged in to the laptop? Well, what do notebook computers use their power cords, voltage transformers, and associated connectors for? They have all these things so they can charge their batteries of course! So, what might happen if a laptops internal battery were to short? Well, the CURRENT running through the power, cord and adapter would shoot up, WAY up. It would shoot up enough to cause the point of most resistance to heat. What is this point you may ask? Well, if there isn't a fusible link in the circuit, it is most likely the point where two conductive surfaces mate, in other words, the connector. This also explains why the laptop was replaced. Most likely cause was defective Lion polymer batteries. Now, before you bloggers starts doing the my computer-is-better-than yours dance. Guess what folks, nearly every new laptop and cell phone made is currently using this type of battery. (And, soon, they are coming to your cars!) Failures of this type of battery are fairly common and unfortunately, fairly dangerous. Lithium explodes and burns very hot, and like phosphorous, it is difficult to extinguish. Don't believe me? Try burning one! I'd advise you do it outside. Or, you could just ask, Apple, Sony Ericsson, Motorola, Nokia, Dell or Toyota. (Just to name a few off the top of my head) All of these companies have had Lion related problems in the past. So, what do I think? Not an entirely usual problem however unfortunate.