According to the Merriam-Webster online dictionary, it means:
: malicious, spiteful, or overbearing behavior; also : an instance of such behavior
In a colloquial sense, it can also mean a crappy, confusing, vaguely menacing or generally wrong situation (many of the people I know would be cruder and say 'f**kery'). This is the sense in which I took Mr. King's tweet (I could be wrong--I certainly can't speak for him), based upon how it's used by friends of mine from Mass.--it's a regional thing. The problem with using a word that's generally unfamiliar is that people read into it meaning and intent that isn't there.
As far as the situation he was commenting on, I have no opinion. I don't like Mr. Allen's movies, and I don't much pay attention to gossip.
Sorry I didn't reply in a timely manner--sick LilMan means not much internet time for me