>(Gawker also changed its story, but proof of the original headline is still in the URL)

You can put anything in the URL you like, as long as the number matches and it passes whatever regular expression gawker runs on those URLs, it will point to the right news story. Hardly conclusive proof that gawker changed the headline when someone can do something like http://gawker.com/5968551/ryan-lanza-is-a-cold-blooded-murde... and the URL bar doesn't even change to reflect the original title.