Deleted from what? The New Testament has no single autograph to which one could compare. What you mean is that they made different choices than the KJV, which is to be expected in a new translation. If you're reading an authorized copy of the NIV, none of those verses are entirely unmentioned, you just need to look down at the footnotes, where they explain the multiple manuscripts problem.
The link is pretty funny, though! "Unspoken" indeed. As though the KJV-only crowd could ever be convinced to stop yammering about the scholastic superiority of Medieval witch-burners.