since its the edge of the socket it could very well be insulation... you do use the socket metal thing to clamp down the cpu, right? its leg is right next to those pins, and condensation will form on that metal and then possibly run down into the socket, bam... im not convinced thats what happended, but if you guys had the same thing happen at the same location of the socket... thats not a coincidence... and i doubt vcore is any diferent on those pins then on other vcore and vss pins... so i dont think its some electrical anomally that causes this...

and yeah, modern cpus are really beefy on vcore pins, vtt is their achilles heel, on vcore pins you can roast them for a while before they give up, the only nehalem cpu i heard of that died from vcore for sure was in foxconns labs and it was with 2.4v on air
instant shutdown and dead...