Spark plugs turning?
 

I discovered a problem when I was checking on my spark plugs. I'm turbo'd for the past 600 miles. So, I decided to see how my plugs look. I found that the porcelain spins, which is not supposed to. I checked the others and they do the same thing. They r Denso plugs. WTF is going on? Has this happened to you guys? Is it because they are running too hot? The tips look brownish.

Any help would be appreciated.