haha. The term "having it out for" has largely replaced "having it in for" just about everywhere I see that phraseology being used. I just don't understand how that suddenly became the way to say it.

It's the same way that the term "dropping" a new song has now become the way many people refer to anything being publicly disclosed. I actually wrote a NY Times reporter who said that a lawsuit had been "dropped" when she meant it had been FILED -- because dropping a lawsuit means it is not longer set to be adjudicated.